JP2020177026A - Water content observation device, water content observation method and cultivation device - Google Patents

Abstract

To control the water content contained in plants including fruits, such as tomato, flexibly in consideration of the effect of the surrounding environmental conditions.SOLUTION: A first projection light source irradiates the leaves of a plant with 905 nm near infrared light having a characteristic hard to be absorbed by water as a reference light. A second projection light source irradiates the leaves of a plant with 1550 nm near infrared light having a characteristic easy to be absorbed by water as a measuring light. The threshold setting/water index detection processing part calculates the water index of one leaf which is the sum of reflection intensity ratios ΣLn (I905/I1550). The control part is connected to a control device 200 that controls the environmental conditions around the plant, and instructs the control device 200 to change or maintain an environmental condition based on the calculated change in the water content in the plant.SELECTED DRAWING: Figure 37

Description

The present invention relates to a water content observing device for observing the water content contained in a plant, a water content observing method, and a cultivation device.

Conventionally, it is known that in a normal plant, a potential difference exists inside and outside the cell, and an electromotive force is generated. The mechanism by which such electromotive force is generated can be explained, for example, based on an electrophysiological model of the axial organs of higher plants. In particular, various methods have been proposed for non-destructively investigating the state of plant roots (for example, water stress) by utilizing the electromotive force between the roots and the soil.

For example, Patent Document 1 is known as a prior art for measuring water stress in a plant using the above method. In Patent Document 1, a first non-polar electrode is connected to a plant, a second non-polar electrode is connected to the soil in which the plant is planted, and a potentiometer is provided between these two non-polar electrodes. By measuring the electromotive force between both non-polarizing electrodes with this potentiometer, the water stress received by the plant can be measured.

Japanese Unexamined Patent Publication No. 2001-272373

As an example of a plant, in order to improve the sugar content of fruits such as tomatoes, the amount of water contained in tomato leaves and the like is usually considered. However, the water content of tomato leaves and the like is not determined solely by the water provided by manual irrigation by the grower (farmer) or automatic irrigation by an irrigation device (for example, a sprinkler), and the surrounding environmental conditions (for example, temperature, etc.). It is known that it fluctuates under the influence of humidity). The above-mentioned Patent Document 1 does not pay attention to such a property, and it is not possible to specifically control the water content of tomato leaves and the like in consideration of the influence of the surrounding environmental conditions.

In addition, in order to increase the value (that is, unit price) of tomatoes, it is conceivable to increase the sugar content of tomatoes, but in order to increase this sugar content, at what timing and how much irrigation should be performed? Was largely due to artificial arrangements such as the farmer's past experience and intuition.

In general, increasing the sugar content of fruits such as tomatoes leads to improved quality and increases the unit price, but on the other hand, it may not be easy to grow, so the yield decreases and the production volume decreases. The sides are strong. In other words, there is a trade-off between fruit sophistication and yield. Therefore, it is expected that the yield will be improved and the productivity will be increased in the future.

Further, as described in Patent Document 1, when an electrode is connected to a plant or soil for measurement, there is a concern that the roots of the plant or the like may be damaged depending on the measurement time.

The present invention has been made in view of the above-mentioned conventional situation, and can flexibly control the amount of water contained in a plant containing fruits such as tomatoes in consideration of the influence of surrounding environmental conditions. An object of the present invention is to provide a water content observation device, a water content observation method, and a cultivation device.

The present invention is a water content observing device for observing the amount of water contained in a plant, and is a first light source that irradiates the plant with reference light having a first wavelength having a characteristic of being difficult to be absorbed by water by optical scanning. And the second light source that irradiates the plant with the measurement light of the second wavelength having the property of being easily absorbed by water by the optical scanning, and the reference light reflected by the plant during a certain measurement period. A water content calculation unit that repeatedly calculates the water content contained in the plant based on the reflected light and the reflected light of the measurement light reflected by the plant, and an environmental control device that controls the environmental conditions around the plant. A control unit that instructs the environmental control device to change or maintain the environmental conditions based on the transition of the increase / decrease in the water content contained in the plant calculated by the water content calculation unit. A water content observation device is provided.

In addition, the present invention provides the plant with a predetermined amount of water based on the water content observation device and the time-series transition of the water content calculated by the water content calculation unit during a part of the measurement period. Provided is a cultivation apparatus including a cultivation control unit for irrigating water.

Further, the present invention is a method for observing the amount of water in a water amount observing device for observing the amount of water contained in a plant, and refers to a first wavelength having a characteristic that the first light source is hardly absorbed by water by optical scanning. The light is irradiated toward the plant, and the second light source irradiates the plant with measurement light having a second wavelength having a characteristic of being easily absorbed by water by the optical scanning, and the light is irradiated toward the plant for a certain measurement period. Based on the reflected light of the reference light reflected by the plant and the reflected light of the measured light reflected by the plant, the amount of water contained in the plant is repeatedly calculated to control the environmental conditions around the plant. Provided is a method for observing the amount of water, which is connected to the environmental control device and instructs the environmental control device to change or maintain the environmental conditions based on the calculated transition of increase / decrease in the amount of water contained in the plant.

According to the present invention, it is possible to flexibly control the amount of water contained in a plant containing fruits such as tomatoes in consideration of the influence of surrounding environmental conditions.

Conceptual explanatory diagram showing an example of the usage situation of the plant detection camera of each embodiment A block diagram showing a configuration example of a plant observation system in which a plant detection camera of each embodiment is arranged in a greenhouse together with a control device for controlling environmental conditions in the greenhouse. Block diagram showing in detail an example of the internal configuration of a plant detection camera The figure which shows in detail an example of the internal structure of the image judgment part of a plant detection camera Flow chart explaining an example of initial setting operation in the control unit of the plant detection camera Illustrated diagram of the principle of moisture detection in an invisible light sensor Graph showing an example of the spectral characteristics of near-infrared light with respect to water (H ₂ O) A flowchart illustrating an example of a detailed operation procedure for detecting water contained in plant leaves with an invisible light sensor. A flowchart illustrating an example of the procedure for calculating the moisture index in steps S18-5. The figure explaining an example of the measurement method of the comparative example (A) A graph showing an example of the intensity of reflected light with respect to the wavelength of near-infrared light when the leaves were irradiated with near-infrared light outdoors, and (B) a white background plate bd was installed indoors and outdoors. A graph showing an example of the intensity of reflected light with respect to the wavelength of near-infrared light when the leaves are irradiated with near-infrared light. Explanatory drawing of an example of how to attach leaves to a white background plate Graph showing an example of time change of standardized pixel average moisture index in the first water potential control experiment Graph showing an example of time change of standardized pixel average moisture index in the second water potential control experiment Graph explaining an example of irrigation amount and irrigation timing A flowchart illustrating an example of the optimum irrigation amount search procedure of the first embodiment. The figure which shows an example of the user interface (UI) screen about water potential control. Diagram showing an example of the search irrigation amount input screen popped up on the UI screen Flow chart explaining an example of the water stress control (cultivation control) procedure of the first embodiment (A)-(D) A diagram schematically showing an example of a water stress profile. A flowchart illustrating an example of the optimum irrigation amount search procedure in the first modification of the first embodiment. (A) A diagram showing an image showing the water content of the leaf to be measured and showing an example of an image of the leaf before the misalignment, taken by the plant detection camera of the second embodiment, (B) second. The figure which shows the image which shows the water content of the leaf to be measured, and shows an example of the image of the leaf after the misalignment, which is taken by the plant detection camera of embodiment. A graph showing an example of the time change of the standardized pixel average moisture index in the water potential control experiment when the position shift occurs. A table showing an example of the standardized pixel average moisture index before and after position shift correction in chronological order A flowchart illustrating an example of the position deviation correction procedure of the second embodiment. (A) It is a figure which shows the white background plate used for detecting the positional deviation in the modification 1 of the 2nd Embodiment, and is the front view of the white background plate, (B) is the modification of the 2nd Embodiment. A diagram showing a white background plate used for detecting the positional deviation in 1 is shown, and a side view of the white background plate shown in (A). The figure explaining an example of the mechanical arrangement of the white background board and the plant detection camera in the modification 2 of the 2nd Embodiment. (A) Frame image of tomato foliage, (B) (A) A diagram showing the occupied space of leaves obtained when the shooting distance is 3 m and the threshold value is set to 0.05 with respect to the visible light image of (A). (C) A diagram showing the occupied space of leaves obtained when the shooting distance is 1 m and the threshold value is set to 0.3 with respect to the visible light image of (A). A flowchart illustrating an example of the threshold setting procedure Graph showing frequency distribution of reflection intensity ratio in all pixels Explanatory drawing showing an example of the relationship between temperature, relative humidity and saturation Explanatory drawing showing an example of the transition of leaf transpiration due to changes in temperature and relative humidity. (A)-(D) Diagrams schematically showing examples of water stress profiles based on leaf transpiration due to changes in temperature and relative humidity. A diagram showing another example of a user interface (UI) screen related to water potential control. The figure which shows an example of the fixed value setting input screen of the environment control mode specified in the UI screen shown in FIG. The figure which shows an example of the saturation setting program input screen of the environment control mode specified in the UI screen shown in FIG. 34. A flowchart illustrating an example of a control operation procedure for the ambient environmental conditions of the plant according to the third embodiment.

Hereinafter, each embodiment in which the water content observation device, the cultivation device, and the water content observation method according to the present invention are specifically disclosed will be described in detail with reference to the drawings as appropriate. However, more detailed explanation than necessary may be omitted. For example, detailed explanations of already well-known matters and duplicate explanations for substantially the same configuration may be omitted. This is to avoid unnecessary redundancy of the following description and to facilitate the understanding of those skilled in the art. It should be noted that the accompanying drawings and the following description are provided for those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

(First Embodiment)
As an example of the water content observation device of the present embodiment, the plant detection camera 1 shown in FIG. 1 will be illustrated and described. Further, the cultivation device of the present embodiment is an example of the plant detection camera 1 shown in FIG. 1 and a cultivation control unit that supplies fertilizer (for example, liquid fertilizer, that is, liquid fertilizer) or irrigates a plant with a predetermined amount of water. The fertilizer water supply device WF of the above and a monitor 50 for displaying a user interface screen 60 (see FIG. 17) and the like are included. The present invention can also be expressed as a water content observation method for executing each process performed by the plant detection camera 1. The plant detection camera 1 of the present embodiment can detect the distribution state of the presence or absence of water in the plant.

Here, the observation target of the plant detection camera 1 of the present embodiment is a plant, and more specific examples will be described by exemplifying fruits and vegetables. For example, in the growth of fruit vegetables such as tomatoes, in order to increase the sugar content of tomato fruits, the water and fertilizer of the roots and leaves are digested in an appropriate amount in photosynthesis, and as a result, the water and fertilizer are sufficiently supplied. It is known that it is necessary to run out of water and fertilizer. For example, if the leaves are sufficiently hydrated, the leaves will be in a healthy and flat shape. On the other hand, if the water content of the leaves is considerably insufficient, the shape of the leaves will be warped. On the other hand, if there is a considerable shortage of fertilizer in the soil, symptoms such as yellowing of the leaves will occur.

In the following embodiment, the plant detection camera 1 irradiates a plant (for example, a leaf) with a plurality of types of laser light having different wavelengths, and based on the intensity ratio of each diffusely reflected light reflected at the irradiation position of the leaf. An example of detecting the water content of leaves will be described. In the present embodiment, the leaves of the plant are measured, but the measurement target is not limited to the leaves, but other parts such as fruits, stems, and flowers may be used. This also applies to the second embodiment.

(Overview of plant detection camera)
FIG. 1 is a conceptual explanatory view showing an example of a usage situation of the plant detection camera 1 of each embodiment. The plant detection camera 1 is installed at a fixed point in a greenhouse in which fruits and vegetables such as tomatoes are vegetated. Specifically, the plant detection camera 1 is installed, for example, on a base BS fixed to a mounting jig ZG mounted so as to sandwich a columnar column MT1 extending vertically upward from the ground. There is. The plant detection camera 1 operates by being supplied with power from the power switch PWS attached to the support column MT1 and emits reference light LS1 and measurement light LS2 which are a plurality of types of laser light having different wavelengths toward the plant PT to be observed. Irradiate over the irradiation range RNG.

The plant PT is a fruit vegetable plant such as tomato, and roots are grown from the soil SL filled in the soil pot SLP installed on the base BB, and the stem PT1, the stem PT2, the leaf PT3, and the fruit. It has PT4 and flower PT5, respectively. A fertilizer water supply device WF is installed on the base BB. The fertilizer water supply device WF supplies water to the soil pot SLP via, for example, a cable WL, according to an instruction from the wireless communication system RFSY connected via a LAN (Local Area Network) cable LCB2. As a result, water is supplied to the soil SL, so that the roots of the plant PT absorb water, and each part in the plant PT (that is, trunk PT1, stem PT2, leaf PT3, fruit PT4, flower PT5). Is supplied with water.

Further, the plant detection camera 1 receives the diffuse reflection light RV1 and RV2 reflected at the irradiation position of the plant PT irradiated with the reference light LS1 and the measurement light LS2, and further receives the ambient light RV0. As will be described later, the plant detection camera 1 has a normal camera function, and an image within a predetermined angle of view (that is, a visible light image of the plant PT in the vinyl house shown in FIG. 1) due to the incoming light of the ambient light RV0. ) Can be imaged. The plant detection camera 1 outputs output data including various detection results (see below) and image data based on the diffuse reflection light RV1 and RV2 to the data logger DL.

The data logger DL transmits the output data from the plant detection camera 1 via the LAN cable LCB1 and the wireless communication system RFSY to the management PC (Personal Computer) of the control room in the office located geographically separated from the vinyl house. Send to (not shown). The wireless communication system RFSY controls communication between the data logger DL in the vinyl house and the management PC in the control room in the office, and further, water and fertilizer to the soil pot SLP, although the communication specifications are not particularly limited. The instruction from the management PC regarding the supply is transmitted to the fertilizer water supply device WF.

A monitor 50 is connected to the management PC in the control room in the office, and the management PC displays the output data of the plant detection camera 1 transmitted from the data logger DL on the monitor 50. In FIG. 1, for example, the monitor 50 displays the entire plant PT to be observed and the distribution state regarding the presence or absence of water in the entire plant PT. Further, the monitor 50 has an enlarged distribution state of a specific designated portion (that is, a designated portion ZM designated by the zoom operation of the observer using the management PC) in the entire plant PT and image data corresponding to the designated portion. And are generated and displayed so that they can be compared. Further, the monitor 50 as an example of the display unit displays the UI screen 60 including the leaf moisture monitoring screen Gm1 (see FIG. 17), which will be described later.

The plant detection camera 1 has a configuration including a visible light camera VSC and a non-visible light sensor NVSS. The visible light camera VSC (acquisition unit) uses ambient light RV0 for visible light having a predetermined wavelength (for example, 0.4 to 0.7 μm), like an existing surveillance camera, and uses a plant PT in a vinyl house. To image. Hereinafter, the image data of the plant captured by the visible light camera VSC is referred to as "visible light camera image data".

The invisible light sensor NVSS projects reference light LS1 and measurement light LS2, which are invisible light (for example, infrared light) having a plurality of wavelengths (see below), onto the same plant PT as the visible light camera VSC. .. The invisible light sensor NVSS uses the intensity ratio of the diffusely reflected light RV1 and RV2 reflected at the irradiation position of the plant PT irradiated with the reference light LS1 and the measurement light LS2 to obtain the moisture content at the irradiation position of the plant PT to be observed. Detects the presence or absence of.

Further, the plant detection camera 1 uses the visible light camera image data captured by the visible light camera VSC as output image data (hereinafter referred to as “detection result image data”) corresponding to the water content detection result of the invisible light sensor NVSS. Detection result Generates and outputs display data that combines information related to image data. The display data is not limited to the image data obtained by synthesizing the detection result image data and the visible light camera image data, and may be, for example, image data generated so that the detection result image data and the visible light camera image data can be compared. The output destination of the display data from the plant detection camera 1 is, for example, an externally connected device connected to the plant detection camera 1 via a network (not shown), and is a data logger DL or a communication terminal MT (see FIG. 3). .. This network may be a wired network (for example, an intranet or the Internet) or a wireless network (for example, a wireless LAN).

(Plant observation system with a plant detection camera installed in a greenhouse)
Next, a configuration example of the plant observation system 1000 in which the plant detection camera 1 of each embodiment is installed in the vinyl house VGH will be described with reference to FIG. FIG. 2 is a block diagram showing a configuration example of a plant observation system 1000 in which the plant detection camera 1 of each embodiment is arranged in the vinyl house VGH together with a control device 200 for controlling the environmental conditions of the vinyl house VGH. .. Regarding the details of the operation of each part of each part shown in FIG. 2 except for the plant detection camera 1 and the air conditioner 227, a published document filed by the same applicant as the present application (specifically, Japanese Patent Application Laid-Open No. 2014-57570). No.) may be incorporated in the present specification with reference to the publication. Here, the plant detection camera 1 is installed in the greenhouse VGH in a situation where the environmental conditions (for example, temperature and humidity) around the plants (for example, fruits such as tomatoes) grown in the greenhouse VGH can be changed. A configuration example of the installed plant observation system 1000 will be described.

The plant observation system 1000 shown in FIG. 2 includes a plant detection camera 1, a control device 200, an environment sensor 211, on-off valves 213 and 215, a water supply pump 217, side windows 219, a ventilation device 221 and a ceiling curtain. The configuration includes 223, a side curtain 225, and an air conditioner 227. The control device 200 has a role as an environmental control device capable of maintaining and changing the environmental conditions (for example, temperature and humidity) around the plants grown in the vinyl house VGH. The control device 200 has a configuration including an I / F unit 201, a built-in clock 203, an arithmetic processing unit 205, and a storage unit 207. The storage unit 207 has a first storage unit 207a, a second storage unit 207b, and a third storage unit 207c.

The main body of the vinyl house VGH is formed, for example, with an inverted U-shaped cross section, a roof portion having a semicircular cross section, a pair of side wall portions facing each other supporting the roof portion, and a pair of side wall portions orthogonal to the side wall portions and facing each other. It is equipped with a gable wall. Hereinafter, the direction passing through the pair of gable walls is referred to as the longitudinal direction, and the direction passing through the pair of side wall portions is referred to as the lateral direction. The shape of the main body of the above-mentioned vinyl house VGH is an example, and is not limited to that shape.

The environment sensor 211 measures the room temperature in the vinyl house VGH around the plant PT and the underground temperature of the soil SL in which the plant PT is sown, as the ambient temperature of the plant PT. Further, it is preferable that the environment sensor 211 includes a humidity sensor that measures the humidity around the plant PT and an illuminance sensor that measures the illuminance around the plant PT. The environment sensor 211 outputs the measurement result (for example, the temperature and humidity around the plant PT) to the control device 200.

In the vinyl house VGH, a water supply device (not shown) including a water sprinkling device and a mist device is provided in order to sprinkle water on the community of plant PTs grown in the vinyl house VGH. The water sprinkling device includes two water sprinkling tubes, and when water is passed through the water sprinkling tubes, water is ejected in the form of a shower or a fountain through the water passage holes. The two water sprinkling tubes are laid along a pair of side wall portions of the vinyl house VGH over a substantially total length in the longitudinal direction of the vinyl house VGH. Further, the mist device includes a mist tube, and the mist tube has a large number of nozzles attached to a pipe wall through which water is passed, and when water is passed, water is sprayed from the nozzles.

This water supply device is an on-off valve composed of a solenoid valve on a flow path for supplying water to the water sprinkling device and the mist device in order to individually control the timing of ejecting water or hot water from each of the water sprinkling device and the mist device. It includes 213 and 215. The on-off valves 213 and 215 are individually controlled via the I / F unit 201 of the control device 200, and whether or not to supply water or hot water to the water sprinkling device and the mist device is individually selected. The water or hot water supplied to the water sprinkling device and the mist device is pressurized to a predetermined pressure by the water supply pump 217.

The main body of the vinyl house VGH is in a closed state where the external light (for example, sunlight) incident from the roof is dimmed, and the plant PT is irradiated without dimming the external light (for example, sunlight) incident from the roof. A ceiling curtain 223 that can be opened and closed between the open state and the open state is attached.

A side window 219 that can be opened and closed is formed on the side wall of the main body of the vinyl house VGH, and by adjusting the opening amount of the side window 219, the ventilation resistance of air when taking in outside air into the main body of the vinyl house VGH Is adjusted. Further, a side curtain 225 is arranged in addition to the side window 219 on the side wall portion of the main body of the vinyl house VGH.

The side curtain 225 is a closed state that dims the external light (for example, sunlight) incident from the side wall portion of the main body of the vinyl house VGH, and the plant without dimming the external light (for example, sunlight) incident from the side wall portion. It is configured to be openable and closable with the open state where the PT is irradiated. The ceiling curtain 223, the side curtain 225, and the side window 219 are driven by the control device 200. When the ceiling curtain 223 and the side curtain 225 are opened and closed, the amount of heat flowing into the main body of the vinyl house VGH is adjusted. By opening and closing the ceiling curtain 223 and the side curtain 225, the inside of the main body of the vinyl house VGH is opened and closed. The rate of temperature rise in space is regulated. Further, by adjusting the opening amount of the side window 219, the speed at which the outside air is taken into the main body of the vinyl house VGH is adjusted. The ceiling curtain 223 and the side curtain 225 mainly contribute to the adjustment of the amount of heat incident on the internal space of the main body of the vinyl house VGH. Further, the side window 219 is used when the temperature is adjusted by taking in the outside air into the internal space of the main body of the vinyl house VGH and utilizing the temperature difference between the inside and outside of the main body of the vinyl house VGH.

The ventilator 221 is located above the pair of gable walls to form an air flow around the plant PT. The ventilation device 221 is operated as needed, and when the side window 219 is open, the ventilation device 221 is operated so that the outside air can be forcibly taken into the main body of the vinyl house VGH. The ventilation device 221 may be either a ventilation fan for exhausting air from the main body of the vinyl house VGH or a blower for taking in outside air into the main body of the vinyl house VGH. The blower is arranged inside the main body of the vinyl house VGH, and it is also possible to forcibly form an air flow around the plant PT and regulate the humidity around the plant PT. Further, if necessary, the air conditioner 227 may be arranged in the vinyl house VGH. The air conditioner 227 has a role of adjusting the temperature and humidity in the vinyl house VGH.

The environment in which the plant PT grows in the main body of the vinyl house VGH controls the side window 219, the ventilation device 221, the ceiling curtain 223, the side curtain 225, the air conditioner 227, and the like, in addition to the water supply device (not shown) described above. It changes depending on the situation. The control device 200 is an environmental control device for controlling the environmental conditions (for example, temperature and humidity) around the plant PT, in addition to the water supply device (not shown) described above, a side window 219, a ventilation device 221 and a ceiling curtain. It controls 223, side curtain 225, air conditioner 227, and the like.

The control device 200 opens and closes the on-off valves 213 and 215, adjusts the water supply pressure and water temperature of the water supply pump 217, opens and closes the ceiling curtain 223 and the side curtain 225, adjusts the opening amount of the side window 219, and operates and stops the ventilation device 221. , Control ventilation to the air duct (not shown). An electromagnetic contactor (electromagnetic relay) that turns on and off the power supply to each device is used to start and stop energization of each of these devices. The control device 200 is housed in a housing attached to the main body of the vinyl house VGH to form a control panel. Further, the control device 200 acquires environmental condition information (for example, temperature information and humidity information) from the environment sensor 211 at a predetermined cycle, and acquires the acquired environmental condition information and instruction information from the plant detection camera 1 (see below). The above-mentioned control is performed using. The specific operation of the control device 30 will be described later. The control device 200 includes a device such as a microcomputer that operates according to a program as a main hardware element.

For example, the control device 200 is configured as a personal computer, receives the output of the environment sensor 211 through the I / F unit 201, and gives an instruction to each device. That is, the control device 200 can control each device by executing the program. The control device 200 may be configured as a dedicated device instead of a general-purpose personal computer.

As shown in FIG. 2, the control device 200 includes an I / F unit 201 to which each of the above-described devices and the environment sensor 211 are connected, a storage unit 207 that stores various data, and a real-time clock that clocks the date and time. It is equipped with a built-in clock 203. Further, the control device 200 is provided with an arithmetic processing unit 205 that controls each of the above-described devices using the information on the environmental conditions acquired from the environment sensor 211 through the I / F unit 201 and various data stored in the storage unit 207. .. The I / F unit 201 includes an electromagnetic contactor (not shown) for turning on / off the power supply to each device. The time interval for the I / F unit 201 to acquire the information on the environmental conditions from the environment sensor 211 is set to, for example, about 1 to 15 minutes. A device (not shown) that serves as a user interface is connected to the I / F unit 201 so that the user can set the contents to be stored in the storage unit 207, set the time of the built-in clock 203, and the like through this device. is there.

The first storage unit 207a stores the ambient temperature and the amount of water in association with each other according to the growth stage of the plant PT. The second storage unit 207b stores the ambient temperature and the timing of sprinkling in association with each other according to the growth stage of the plant PT. The third storage unit 207c stores the number of days after the plant PT germinates and the environment sensor 211 having a different height position in association with each other.

For example, in order to lower the temperature of the leaf PT3 of the plant PT, the control device 200 includes dimming by the ceiling curtain 223 and the side curtain 225, ventilation or dehumidification by the side window 219, the ventilation device 221 and the air conditioner 227, a watering device and a mist. The water sprinkled by the device is used in combination.

The ceiling curtain 223 and the side curtain 225 not only suppress the rise in the internal temperature of the main body of the greenhouse VGH by dimming, but also suppress the strong light in summer, so that the effect of efficiently performing photosynthesis of plant PT. Can be expected.

The ventilation device 221 and the side window 219 ventilate by discharging the air inside the main body of the vinyl house VGH and taking in the outside air into the main body of the vinyl house VGH to raise the internal temperature of the main body of the vinyl house VGH. Suppress. Further, the air conditioner 227 forms an air flow around the plant PT to promote the transpiration of the plant PT (see below), and further reduces the humidity around the plant PT.

In addition, the watering device and the mist device lower the temperature of the leaf PT3 by sprinkling water, which is lower than the ambient temperature of the plant PT, on the plant PT, and lower the ambient temperature of the plant PT by removing the heat of vaporization. It is used to make it. The watering device contributes to lowering the temperature of the leaf PT3 of the plant PT and the ambient temperature of the plant PT mainly in the lower part of the main body of the greenhouse VGH. The mist device contributes to lowering the temperature mainly in the upper part of the main body of the greenhouse VGH.

When sprinkling water for the purpose of lowering the temperature of the leaves, it is desirable to set the water temperature to about 10 ° C. by a chiller (not shown) in summer. Since it takes a relatively long time for the chiller to reach the set temperature, when using the chiller, consider the time until the water temperature reaches the set temperature, and go back from the timing of supplying water from the water supply device to the plant PT. It is necessary to control the temperature. When the temperature of the plant PT becomes low as in winter, the water temperature may be set to about 15 ° C. by a chiller to raise the temperature of the leaves.

In the present embodiment, as described above, in order to control the environment of the plant PT, dimming by the ceiling curtain 223 and the side curtain 225, ventilation or dehumidification by the side window 219, the ventilation device 221 and the air conditioner 227, and the water sprinkling device. And watering by a mist device are used in combination.

The watering device and the mist device are mainly used for the purpose of supplying water to the plant PT and controlling the ambient temperature of the plant PT. Therefore, the control device 200 controls at least one of the timing and the amount of water sprinkled by the water sprinkling device and the mist device according to the ambient temperature and humidity of the plant PT measured by the environment sensor 211. The timing and amount of water sprinkled with respect to the ambient temperature and humidity of the plant PT detected by the environment sensor 211 are predetermined and stored in the storage unit 207.

Further, the control device 30 is a ventilation device 221 (including an air conditioner 227 if necessary) for the purpose of dehumidification, cooling, ventilation, etc., according to conditions such as temperature, humidity, and illuminance measured by the environment sensor 211. You may operate.

(Explanation of each part of the plant detection camera)
FIG. 3 is a block diagram showing in detail an example of the internal configuration of the plant detection camera 1. The plant detection camera 1 shown in FIG. 3 has a configuration including a non-visible light sensor NVSS and a visible light camera VSC. The invisible light sensor NVSS has a configuration including a control unit 11, a projection unit PJ, and an image determination unit JG. The projection unit PJ includes a first projection light source 13, a second projection light source 15, and an optical unit 17 for scanning the projection light source. The image determination unit JG includes an image pickup optical unit 21, a light receiving unit 23, a signal processing unit 25, a detection processing unit 27, and a display processing unit 29. The visible light camera VSC has an imaging optical unit 31, a light receiving unit 33, an imaging signal processing unit 35, and a display control unit 37. The communication terminal MT is carried by a user (for example, an observer for growing a plant PT of fruits and vegetables such as tomatoes; the same applies hereinafter).

In the description of each part of the plant detection camera 1, the control unit 11, the invisible light sensor NVSS, and the visible light camera VSC will be described in this order.

The control unit 11 is configured by using, for example, a CPU (Central Processing Unit), an MPU (Micro Processing Unit), or a DSP (Digital Signal Processor), and controls the operation of each part of the visible light camera VSC and the invisible light sensor NVSS as a whole. It performs signal processing to control the CPU, data input / output processing with other parts, data calculation processing, and data storage processing. Further, the control unit 11 includes a timing control unit 11a described later (see FIG. 4).

The control unit 11 sets the detection threshold value M of the plant PT to be detected by the invisible light sensor NVSS in the detection processing unit 27 described later. Details of the operation of the control unit 11 will be described later with reference to FIG.

The timing control unit 11a controls the projection timing of the first projection light source 13 and the second projection light source 15 in the projection unit PJ. Specifically, when the timing control unit 11a projects the projected light onto the first projection light source 13 or the second projection light source 15, the timing signal TR for scanning the light source is transmitted to the first projection light source 13 or the second projection light source 15. Output.

Further, the timing control unit 11a alternately outputs the light source emission signal RF to the first projection light source 13 or the second projection light source 15 at the start of a predetermined projection cycle. Specifically, the timing control unit 11a outputs the light source emission signal RF to the first projection light source 13 at the start of the odd-numbered projection cycle, and outputs the light source emission signal RF to the second projection light source at the start of the even-numbered projection cycle. Output to 15.

Next, each part of the invisible light sensor NVSS will be described.

When the first projection light source 13 as an example of the first light source receives the timing signal TR for scanning the light source from the timing control unit 11a of the control unit 11, the timing control unit 11a sends the timing signal TR for each odd-th projection period (default value). The reference light LS1 (for example, near-infrared light), which is a laser beam of invisible light having a predetermined wavelength (for example, 905 nm), is transmitted to the plant via the light source scanning optical unit 17 according to the light source emission signal RF of the above. Project to PT.

The presence or absence of detection of water in the plant PT may be determined by comparing with a predetermined detection threshold value M. The detection threshold value M may be a predetermined value, an arbitrarily set value, and a value based on the intensity of diffuse reflected light acquired in the absence of water (for example, in the absence of water). It may be a value obtained by adding a predetermined margin to the value of the intensity of the acquired diffuse reflected light). That is, the presence or absence of detection of water content may be determined by comparing the detection result image data acquired in the absence of water with the detection result image data acquired thereafter. By acquiring the intensity of the diffusely reflected light in the absence of water in this way, it is possible to set a threshold value suitable for the environment in which the plant detection camera 1 is installed as the detection threshold value M for the presence or absence of water content.

When the second projection light source 15 as an example of the second light source receives the timing signal TR for scanning the light source from the timing control unit 11a of the control unit 11, the timing control unit 11a sends the timing signal TR for each even th projection period (default value). The measurement light LS2 (for example, infrared light), which is a laser beam of invisible light having a predetermined wavelength (for example, 1550 nm), is transmitted to the plant PT via the light source scanning optical unit 17 according to the light source emission signal RF of the above. Project to. In the present embodiment, the measurement light LS2 projected from the second projection light source 15 is used to determine the presence or absence of detection of water in the plant PT. The wavelength of the measurement light LS2 is 1550 nm, which is a wavelength having a characteristic of being easily absorbed by water (see FIG. 7).

Further, the plant detection camera 1 uses the diffuse reflection light RV1 of the reference light LS1 as reference data for detecting the water content at the irradiation position of the plant PT, and the diffuse reflection light at the irradiation position of the plant PT irradiated with the measurement light LS2. Using the RV2 and the diffusely reflected light RV1 of the reference light LS1, the presence or absence of water at the irradiation position of the plant PT irradiated with the reference light LS1 and the measurement light LS2 is detected. Therefore, the plant detection camera 1 uses the reference light LS1 and the measurement light LS2 having two different wavelengths and the diffusely reflected light RV1 and RV2 thereof for detecting the water content in the plant PT with high accuracy. Can be detected.

The projection light source scanning optical unit 17 refers to the reference light LS1 projected from the first projection light source 13 or the measurement light LS2 projected from the second projection light source 15 with respect to the plant PT existing in the detection area of the invisible light sensor NVSS. Is scanned two-dimensionally. As a result, the plant detection camera 1 is irradiated with the reference light LS1 and the measurement light LS2 based on the diffuse reflection light RV2 reflected by the measurement light LS2 at the irradiation position of the plant PT and the diffuse reflection light RV1 described above. The presence or absence of moisture at the irradiation position of

Next, the internal configuration of the image determination unit JG will be described in detail with reference to FIGS. 3 and 4. FIG. 4 is a diagram showing in detail an example of the internal configuration of the image determination unit JG of the plant detection camera 1.

The imaging optical unit 21 is configured by using, for example, a lens, collects light incident from the outside of the plant detection camera 1 (for example, diffuse reflected light RV1 or diffuse reflected light RV2), and collects diffuse reflected light RV1 or diffuse reflected light RV2. Is formed on a predetermined imaging surface of the light receiving unit 23.

The light receiving unit 23 is an image sensor having a peak of spectral sensitivity with respect to the wavelengths of both the reference light LS1 and the measurement light LS2. The light receiving unit 23 converts the optical image of the diffusely reflected light RV1 or the diffusely reflected light RV2 imaged on the imaging surface into an electric signal. The output of the light receiving unit 23 is input to the signal processing unit 25 as an electric signal (current signal). The imaging optical unit 21 and the light receiving unit 23 have a function as an imaging unit in the invisible light sensor NVSS.

The signal processing unit 25 includes an I / V conversion circuit 25a, an amplifier circuit 25b, and a comparator / peak hold processing unit 25c. The I / V conversion circuit 25a converts a current signal (analog signal), which is an output signal (analog signal) of the light receiving unit 23, into a voltage signal. The amplifier circuit 25b amplifies the level of the voltage signal, which is the output signal (analog signal) of the I / V conversion circuit 25a, to a level that can be processed by the comparator / peak hold processing unit 25c.

The comparator / peak hold processing unit 25c binarizes the output signal of the amplifier circuit 25b according to the comparison result between the output signal (analog signal) of the amplifier circuit 25b and a predetermined threshold value, and sets the threshold value / moisture index detection processing unit. Output to 27a. Further, the comparator / peak hold processing unit 25c includes an ADC (Analog Digital Converter), detects and holds the peak of the AD (Analog Digital) conversion result of the output signal (analog signal) of the amplifier circuit 25b, and further, the peak. Information is output to the threshold setting / moisture index detection processing unit 27a.

The detection processing unit 27 includes a threshold value setting / moisture index detection processing unit 27a, a memory 27b, and a detection result filter processing unit 27c. The threshold value setting / moisture index detection processing unit 27a creates and registers frequency distribution data in advance. The frequency distribution data shows the frequency distribution of the reflection intensity ratio in all pixels of a one-frame image. As an example of the threshold value calculation unit, the threshold value setting / moisture index detection processing unit 27a calculates and sets the threshold value Sh of the reflection intensity ratio for identifying the leaf shape using this frequency distribution data, as will be described later. To do.

Further, the threshold setting / moisture index detection processing unit 27a includes the output (peak information) of the comparator / peak hold processing unit 25c in the diffuse reflection light RV1 of the reference light LS1 and the comparator / peak in the diffuse reflection light RV2 of the measurement light LS2. Based on the output (peak information) of the hold processing unit 25c, the presence or absence of water at the irradiation positions of the reference light LS1 and the measurement light LS2 of the plant PT is detected.

Specifically, the threshold setting / moisture index detection processing unit 27a temporarily stores the output (peak information) of the comparator / peak hold processing unit 25c in the diffuse reflection light RV1 of the reference light LS1 in the memory 27b. Next, it waits until the output (peak information) of the comparator / peak hold processing unit 25c in the diffuse reflection light RV2 of the measurement light LS2 is obtained. After the output (peak information) of the comparator / peak hold processing unit 25c in the diffuse reflection light RV2 of the measurement light LS2 is obtained, the threshold setting / moisture index detection processing unit 27a refers to the memory 27b and within the angle of view. Output (peak information) of the comparator / peak hold processing unit 25c in the diffuse reflection light RV1 of the reference light LS1 in the same line of the plant PT and the comparator / peak hold processing unit 25c in the diffuse reflection light RV2 of the measurement light LS2. Calculate the ratio to the output (peak information) of.

For example, at an irradiation position where moisture is present, a part of the measurement light LS2 is easily absorbed, so that the reflection efficiency at the irradiation position is lowered and the intensity (that is, amplitude) of the diffuse reflected light RV2 is attenuated. Therefore, the threshold setting / moisture index detection processing unit 27a determines the calculation result for each line of the plant PT included in the angle of view (for example, the difference in intensity between the diffusely reflected light RV1 and the diffusely reflected light RV2 (difference in amplitude ΔV)). Based on the calculation result or the intensity ratio of the diffuse reflected light RV1 and the diffuse reflected light RV2), the presence or absence of water at the irradiation positions of the reference light LS1 and the measurement light LS2 can be detected.

The threshold value setting / moisture index detection processing unit 27a includes an amplitude difference (VA-VB) and an amplitude VA between the diffuse reflection light RV1 of the reference light LS1 and the amplitude VB of the diffuse reflection light RV2 of the measurement light LS2. The presence or absence of water at the irradiation positions of the reference light LS1 and the measurement light LS2 of the plant PT may be detected according to the magnitude comparison between the ratio RT and the predetermined detection threshold value M (see FIG. 6).

Further, the threshold setting / moisture index detection processing unit 27a calculates the intensity ratio of the diffuse reflection light RV1 and the diffuse reflection light RV2, that is, the reflection intensity ratio (also referred to as a measured value) Ln (I ₉₀₅ / I ₁₅₅₀ ), and this reflection From the total of the intensity ratio Ln (I ₉₀₅ / I ₁₅₅₀ ), the total water index corresponding to the amount of water contained in the leaves is obtained. The reflection intensity ratio Ln (I ₉₀₅ / I ₁₅₅₀ ) is, for example, 1 of all the pixels constituting one frame of the visible light image captured by the visible light camera VSC or the invisible light image obtained by the invisible light sensor NVSS. In all the pixels constituting the frame, for example, it is calculated for each predetermined number of pixels (1 × 1 pixel, 4 × 4 pixels), and is expressed as a reflection intensity ratio W1 to Wk for each predetermined number of pixels.

The memory 27b is configured by using, for example, a RAM (Random Access Memory), and temporarily stores the output (peak information) of the comparator / peak hold processing unit 25c in the diffuse reflection light RV1 of the reference light LS1.

The detection result filter processing unit 27c extracts information on the water content detection result from the plant detection camera 1 after filtering out extra components such as noise, based on the output of the threshold value setting / moisture index detection processing unit 27a. The detection result filter processing unit 27c outputs information regarding the extraction result to the display processing unit 29. For example, the detection result filter processing unit 27c outputs information regarding the detection result of water content at the irradiation positions of the reference light LS1 and the measurement light LS2 of the plant PT to the display processing unit 29.

Using the output of the detection result filter processing unit 27c, the display processing unit 29 uses an invisible light image (invisible light image) showing the position of the water content at the irradiation position for each distance from the plant detection camera 1 as an example of information on the water content at the irradiation position. The data of the detection result image) is generated. The display processing unit 29 outputs the detection result image data including the information on the distance from the plant detection camera 1 to the irradiation position to the display control unit 37 of the visible light camera VSC. The non-visible light image may not include information on the distance from the plant detection camera 1 to the irradiation position.

Next, each part of the visible light camera VSC will be described. The imaging optical unit 31 is configured by using, for example, a lens, collects the ambient light RV0 from within the angle of view of the plant detection camera 1, and forms the ambient light RV0 on a predetermined imaging surface of the light receiving unit 33.

The light receiving unit 33 is an image sensor having a peak of spectral sensitivity with respect to a wavelength of visible light (for example, 0.4 μm to 0.7 μm). The light receiving unit 33 converts the optical image formed on the imaging surface into an electric signal. The output of the light receiving unit 33 is input to the imaging signal processing unit 35 as an electric signal. The imaging optical unit 31 and the light receiving unit 33 have a function as an imaging unit in the visible light camera VSC.

The image pickup signal processing unit 35 uses the electric signal output from the light receiving unit 33 to generate visible light image data defined by human-recognizable RGB (Red Green Blue), YUV (luminance / color difference), or the like. .. As a result, the visible light image data captured by the visible light camera VSC is formed. The image pickup signal processing unit 35 outputs visible light image data to the display control unit 37.

The display control unit 37 uses the visible light image data output from the imaging signal processing unit 35 and the detection result image data output from the display processing unit 29, and the moisture content is at any position of the visible light image data. When detected, as an example of information on moisture, display data obtained by combining visible light image data and detection result image data, or display data representing visible light image data and detection result image data in a comparable manner is generated. To do. The display control unit 37 (output unit) transmits the display data to, for example, a data logger DL or a communication terminal MT connected via a network to prompt the display.

The data logger DL transmits the display data output from the display control unit 37 to the communication terminal MT or one or more externally connected devices (not shown), and transmits the communication terminal MT or one or more externally connected devices (for example, FIG. 1). Prompt the display of display data on the display screen of the monitor 50) in the control room in the office shown in.

The communication terminal MT is, for example, a portable communication terminal used by an individual user, receives display data transmitted from the display control unit 37 via a network (not shown), and receives a display screen (not shown) of the communication terminal MT. Display the display data in (shown).

(Explanation of an example of initial operation in the control unit of the invisible light sensor)
Next, an example of the initial operation of the control unit 11 of the invisible light sensor NVSS of the plant detection camera 1 of the present embodiment will be described with reference to FIG. FIG. 5 is a flowchart illustrating an example of the initial setting operation in the control unit 11 of the plant detection camera 1.

When the control unit 11 instructs the threshold value setting / moisture index detection processing unit 27a to set the threshold value Sh of the reflection intensity ratio for identifying the shape of the leaf, the threshold value setting / moisture index detection processing unit 27a causes the threshold value Sh. Is calculated and set (S1). Details of the process of setting the threshold value Sh will be described later with reference to, for example, FIGS. 28 to 30. When the threshold value Sh is a fixed value, the process of step S1 can be omitted.

The control unit 11 sets the moisture detection threshold value M in the detection processing unit 27 of the invisible light sensor NVSS in the threshold value setting / moisture index detection processing unit 27a (S2). It is preferable that the detection threshold value M is appropriately set according to the plant to be detected.

After the processing of step S2, the control unit 11 outputs a control signal for starting the imaging process to each unit of the visible light camera VSC (S3-1). Further, the control unit 11 sets the timing signal TR for scanning the light source for starting the projection of the reference light LS1 or the measurement light LS2 on the first projection light source 13 or the second projection light source 15 as the first projection light source of the invisible light sensor NVSS. Output to 13 or the second projection light source 15 (S3-2). It should be noted that the execution timing of the operation of step S3-1 and the operation of step S3-2 may be earlier or simultaneous.

FIG. 6 is an explanatory diagram of the principle of moisture detection in the invisible light sensor NVSS. For example, if RT> M, the threshold value setting / moisture index detection processing unit 27a may determine that moisture has been detected, and if RT ≦ M, it may determine that moisture is not detected. In this way, the threshold value setting / moisture index detection processing unit 27a detects the presence or absence of moisture according to the comparison result between the ratio RT of the amplitude difference (VA-VB) and the amplitude VA and the detection threshold value M. The influence of noise (for example, ambient light) can be eliminated, and the presence or absence of moisture can be detected with high accuracy.

Figure 7 is a graph showing an example of the spectral characteristics of the near-infrared light for water (H 2 _O). The horizontal axis of FIG. 7 is the wavelength (nm), and the vertical axis of FIG. 7 is the transmittance (%). As shown in FIG. 7, the reference light LS1 of a wavelength 905nm is close to the transmittance of almost 100% water _(H 2 O), it found to have a hard characteristic is absorbed in water. Similarly, the measurement light LS2 of a wavelength of 1550nm, since the transmittance of water _(H 2 O) is close to 10%, it is found to have easily properties are absorbed in water. Therefore, in the present embodiment, the wavelength of the reference light LS1 projected from the first projection light source 13 is set to 905 nm, and the wavelength of the measurement light LS2 projected from the second projection light source 15 is set to 1550 nm.

In the present embodiment, an invisible light image of a leaf is formed even when the projection range of near-infrared light is reduced due to the wilting of the leaf and the thickness of the leaf is increased due to the warp or curl of the leaf. An average value obtained by dividing the total reflection intensity ratio in all pixel regions (that is, each pixel) by the number of pixels (hereinafter referred to as "pixel average moisture index") constitutes an invisible light image of leaves. The sum of the reflection intensity ratios of all the pixels for each pixel (hereinafter referred to as "sum of moisture indexes") is used as an index of the amount of moisture. In addition, the standardized pixel average moisture index (or simply "moisture") is shown by normalizing the value of the pixel average moisture index and the value of the sum of the moisture indexes when water stress is not applied (that is, the initial stage) to 1.0, respectively. It is called "index") and the sum of the standardized moisture indexes. In this way, by expressing the initial value as a relative value with 1.0 as the initial value, the temporal changes in the "pixel average moisture index" and "moisture index sum" between leaves having different angles and leaf thicknesses are easily relative. Can be compared. The average pixel moisture index and the sum of the moisture indexes are calculated using the reflection intensity ratio calculated for each pixel constituting the invisible light image of the leaf. Therefore, the pixel average moisture index is represented by "(the number of pixels constituting the invisible light image of 1 / leaf) x ΣLn (I ₉₀₅ / I ₁₅₅₀ )", and the total moisture index is "ΣLn (I ₉₀₅ / I ₁₅₅₀ )". ) ”, And both have a strong correlation with the water potential (in other words, the amount of water stress applied to the plant). In addition, all the pixel regions constituting the invisible light image of the leaf are, for example, at the beginning of the measurement period, the reflection intensity ratio in the pixel corresponding to the position where the reference light LS1 or the measurement light LS2 is irradiated. Value) is a set of regions that exceed the threshold value Sh. The threshold value Sh may be a preset value or may be calculated according to the method shown in FIG. 29 described later.

(Detailed description of operation regarding moisture detection of invisible light sensor)
Next, a detailed operation procedure for detecting water content in the invisible light sensor NVSS of the plant detection camera 1 will be described with reference to FIG. FIG. 8 is a flowchart illustrating an example of a detailed operation procedure regarding the detection of water contained in the leaf PT3 of the plant PT by the invisible light sensor NVSS. As a premise of the description of the flowchart shown in FIG. 8, the timing control unit 11a outputs the light source scanning timing signal TR to the first light source 13 or the second light source 15, and the plant detection camera 1 outputs the reference light LS1 or It is assumed that the measurement light LS2 is emitted toward the leaf PT3 of the plant PT.

In FIG. 8, the control unit 11 determines whether or not the light source emission signal RF in the odd-numbered projection period is output from the timing control unit 11a (S12). When the light source emission signal RF in the odd-numbered projection cycle is output from the timing control unit 11a (S12, YES), the first projection light source 13 refers to the light source emission signal RF from the timing control unit 11a. The light LS1 is projected (S13). The projection light source scanning optical unit 17 one-dimensionally scans the reference light LS1 on the line in the X direction of the plant PT included in the angle of view of the plant detection camera 1 (S15). At each irradiation position on the line in the X direction where the reference light LS1 is irradiated, the diffuse reflection light RV1 generated by the diffuse reflection of the reference light LS1 is received by the light receiving unit 23 via the imaging optical unit 21 ( S16).

In the signal processing unit 25, the output (electrical signal) in the light receiving unit 23 of the diffuse reflection light RV1 is converted into a voltage signal, and the level of this voltage signal is amplified to a level that can be processed by the comparator / peak hold processing unit 25c ( S17). The comparator / peak hold processing unit 25c binarizes the output signal of the amplifier circuit 25b according to the comparison result between the output signal of the amplifier circuit 25b and a predetermined threshold value and outputs the output signal to the threshold value setting / moisture index detection processing unit 27a. .. The comparator / peak hold processing unit 25c outputs the peak information of the output signal of the amplifier circuit 25b to the threshold value setting / moisture index detection processing unit 27a.

The threshold value setting / moisture index detection processing unit 27a temporarily stores the output (peak information) of the comparator / peak hold processing unit 25c with respect to the diffuse reflection light RV1 of the reference light LS1 in the memory 27b (S18-2). Further, the threshold value setting / moisture index detection processing unit 27a is a comparator / comparator for the same line in the diffuse reflection light RV1 or the diffuse reflection light RV2 with respect to the reference light LS1 or the measurement light LS2 in the previous frame (projection cycle) stored in the memory 27b. The output of the peak hold processing unit 25c is read from the memory 27b (S18-3).

The threshold setting / moisture index detection processing unit 27a includes the output (peak information) of the comparator / peak hold processing unit 25c in the diffuse reflection light RV1 of the reference light LS1 on the same line and the comparator / comparator in the diffuse reflection light RV2 of the measurement light LS2. Based on the output (peak information) of the peak hold processing unit 25c and the predetermined detection threshold value M, the presence or absence of water on the same line is detected (S18-4).

The threshold value setting / moisture index detection processing unit 27a as an example of the water content calculation unit calculates the water content index which is the total sum ΣLn (I ₉₀₅ / I ₁₅₅₀ ) of the reflection intensity ratio (S18-5). Details of the calculation of this water content index will be described later.

The display processing unit 29 uses the output of the detection result filter processing unit 27c to generate detection result image data indicating a moisture detection position. The display control unit 37 outputs the detection result image data generated by the display processing unit 29 and the visible light camera image data of the visible light image captured by the visible light camera VSC (S19). Each operation of steps S15, S16, S17, S18-2 to S18-5, and S19 is executed for each line in the detection area of one frame (projection cycle).

That is, when each operation of steps S15, S16, S17, S18-2 to S18-5, and S19 for one line in the X direction is completed, steps S15, S16, S17, and S18-2 for the next line in the X direction are completed. Each operation of S18-5 and S19 is performed (S20, NO), and thereafter, until each operation of steps S15, S16, S17, S18-2 to S18-5, S19 for one frame is completed, step S15, Each operation of S16, S17, S18-2 to S18-5, and S19 is repeated.

On the other hand, when the execution of each operation of steps S15, S16, S17, S18-2 to S18-5, and S19 is completed for all the lines in one frame (S20, YES), the scanning of the projected light continues. If so (S21, YES), the operation of the invisible light sensor NVSS returns to step S12. On the other hand, when the scanning of the reference light LS1 and the measurement light LS2 is not continued (S21, NO), the operation of the invisible light sensor NVSS ends.

FIG. 9 is a flowchart illustrating an example of the procedure for calculating the moisture index in step S18-5. The threshold setting / moisture index detection processing unit 27a calculates the reflection intensity ratio Ln (I ₉₀₅ / I ₁₅₅₀ ) of all the pixels from one frame of the detection result image data which is the invisible light image data (S31). Here, the measured value of the reflection intensity ratio Ln (I ₉₀₅ / I ₁₅₅₀ ) of each pixel is represented by the reflection intensity ratio W1 to Wk. For example, when an image of near-infrared light is composed of 76,800 (= 320 × 240) pixels, the subscript k of Wk is a variable representing 1 to 76,800.

The threshold value setting / moisture index detection processing unit 27a determines whether or not the reflection intensity ratio Wk for each pixel is larger than the threshold value Sh for identifying the leaf PT3 (S32). The initial value of the threshold value Sh is registered in advance in the threshold value setting / moisture index detection processing unit 27a as an empirical value. The empirical value depends on the specifications of the water content observation device (intensity of irradiation laser light, sensitivity of light receiving element, etc.), water content of the leaf to be measured (around 90%), leaf thickness (for example, 200 μm), indoor / outdoor, etc. It is determined. In particular, in the case of outdoors, it changes depending on how the sun shines and how thick the leaves are, and it changes each time.

For example, as an empirical value, when the shooting distance is 1 m, the threshold value Sh at the time of indoor shooting is set to about 0.3. The threshold value Sh at the time of outdoor shooting is set to about 0.9. Further, when the shooting distance is 3 m, the threshold value Sh at the time of indoor shooting is set to about 0.05. It is preferable to set these threshold values Sh as initial values, compare them with the actual leaf shape to determine whether or not they are optimum, and if not, change the threshold value Sh. Further, as will be described later, it is also possible to perform the calculation process of the threshold value Sh and register the calculated threshold value Sh as an initial value.

In step S32, when the reflection intensity ratio Wk is less than the threshold value Sh, it is assumed that this pixel is a pixel representing a background other than leaves, and the display processing unit 29 displays single-color display data for displaying this pixel in a single color. Generate (S36).

On the other hand, when the reflection intensity ratio Wk is equal to or higher than the threshold value Sh (threshold value or higher) in step S32, the display processing unit 29 displays the pixels in a gradation color corresponding to the reflection intensity ratio Ln (I ₉₀₅ / I ₁₅₅₀ ). (S33). Here, the gradation color corresponding to the reflection intensity ratio Ln (I ₉₀₅ / I ₁₅₅₀ ) can be displayed in n gradations. n is an arbitrary positive number.

Specifically, when the reflection intensity ratio Ln (I ₉₀₅ / I ₁₅₅₀ ) is less than 0.3, that is, when it is equal to or less than the leaf threshold Sh, the pixel is displayed in, for example, white (monochromatic). On the other hand, when the reflection intensity ratio Ln (I ₉₀₅ / I ₁₅₅₀ ) is 0.3 or more and less than 0.4, the pixel is displayed in dark green, for example. Similarly, if it is 0.4 or more and less than 0.5, the pixel is displayed in green. If it is 0.5 or more and less than 0.55, the pixel is displayed in yellow. When it is 0.55 or more and less than 0.6, the pixel is displayed in orange. When it is 0.6 or more and less than 0.75, the pixel is displayed in red. If it is 0.75 or more, the pixel is displayed in purple. In this way, the color of the pixel belonging to the leaf is set to any of the six tones.

If the pixel space occupied by the leaves is not appropriate in light of the actual shape of the leaves, the user may set the threshold value Sh to increase or decrease in predetermined steps (for example, 0.01). Good. Alternatively, the user may activate a process for automatically setting the threshold value Sh, which will be described later, to set an appropriate threshold value Sh.

The threshold value setting / moisture index detection processing unit 27a specifies an arbitrary area as the pixel space occupied by the leaves (S34). The leaf pixels are pixels in which the reflection intensity ratio Ln (I ₉₀₅ / I ₁₅₅₀ ) exceeds the threshold value Sh (here, 0.3). In addition, a rectangular (A × B) area ARE is specified so as to surround the pixel of the leaf. This area ARE is used as a value for determining the size of the leaf. The leaf size may be represented by the number of pixels exceeding the threshold value Sh.

Threshold setting / IMI detection processing section 27a, within the area AREs, measurements (reflection intensity ratio _{Ln (I 905 / I 1550)} ) is greater than the threshold value Sh, the reflection intensity ratio _Ln of (I _{905 / I 1550)} The total water index total ΣLn (I ₉₀₅ / I ₁₅₅₀ ), which is the total, is calculated (S35). By obtaining this total water index ΣLn (I ₉₀₅ / I ₁₅₅₀ ), the amount of water contained in the entire leaf can be known.

Further, in step S35, the threshold value setting / moisture index detection processing unit 27a calculates the number of pixels whose measured value (reflection intensity ratio Ln (I ₉₀₅ / I ₁₅₅₀ )) is larger than the threshold value Sh in the area ARE. The average value (referred to as the pixel average moisture index) can be calculated by dividing the total number of reflection intensity ratios ΣLn (I ₉₀₅ / I ₁₅₅₀ ) by the calculated number of pixels. This average value is a value obtained by dividing the total reflection intensity ratio by the area of the leaf whose outer shape is determined by the threshold value Sh, and is a value obtained by dividing the total reflection intensity ratio in the spot by a certain area of the spot. Is different. After this, the operation of calculating the moisture index ends.

As described above, in the present embodiment, instead of obtaining the reflection intensity ratio for each irradiation position, the reflection intensity ratio for each pixel in the frame image can be obtained, and the moisture index can be accurately calculated from the sum of the reflection intensity ratios for each pixel. .. Therefore, the health of leaves, that is, plants can be accurately determined.

Here, as described above, the leaf threshold value Sh is set to the following value as an initial value. When the plant detection camera 1 is installed indoors and the leaf PT3 is imaged indoors, the threshold value Sh is set to about 0.3 when the photographing distance is empirically 1 m. When the shooting distance is 3 m, the threshold value Sh is set to about 0.05. On the other hand, when imaging outdoors (for example, in a vinyl house VGH), the threshold value Sh is empirically set to about 0.9 because the conditions of outside light (for example, sunlight) fluctuate. FIG. 28 is a diagram showing a leaf occupancy range. FIG. 28 (A) is a frame image of tomato foliage. The interleaf distance is about 1 cm. FIG. 28 (B) shows the occupied space of the leaves obtained when the shooting distance is 3 m and the threshold value Sh is set to 0.05 with respect to the visible light image of FIG. 28 (A). In this case, it can be seen that the leaves partially overlap and the threshold value Sh (= 0.05) is an inappropriately set value. FIG. 28 (C) shows the occupied space of the leaves obtained when the shooting distance is 1 m and the threshold value Sh is set to 0.3 with respect to the visible light image of FIG. 28 (A). In this case, the outer shape of the leaf does not overlap with other leaves, and the occupied space of the leaf is roughly the same as the outer shape of the leaf in the visible light image. In this case, it can be seen that the threshold value Sh (= 0.3) is a correctly set value.

Further, the leaf threshold value Sh may be registered before performing the following processing and performing the water content index calculation processing shown in FIG. FIG. 29 is a flowchart illustrating an example of the threshold setting procedure.

In the threshold value setting / moisture index detection processing unit 27a, the appearance of the green (G) pixel determined to be the color of the leaf occupies the frame image (for example, see FIG. 28 (A)) captured by the visible light camera VSC. The ratio (number of G pixels / total number of pixels) is obtained (S101).

The threshold value setting / moisture index detection processing unit 27a obtains the moisture index corresponding to the appearance rate based on the frequency distribution data of the moisture index (S102). FIG. 30 is a graph showing the frequency distribution of the reflection intensity ratio in all pixels. The frequency distribution data is registered in the threshold value setting / moisture index detection processing unit 27a. Using this frequency distribution data, for example, when the appearance ratio occupied by the green (G) pixel determined to be the color of the leaf is 52%, the water content index is about 0.3.

The threshold value setting / moisture index detection processing unit 27a sets the moisture index obtained in step S102 to the threshold value Sh (S103). After that, the threshold value setting / moisture index detection processing unit 27a ends this processing.

In this way, by using the visible light image captured by the visible light camera VSC, the measured value is Ln (I ₉₀₅ / I ₉₀₅ /) so that the number of occupied pixels of the green (specific color) of the leaf is the same as the number of pixels. By finding the threshold value Sh corresponding to the cumulative frequency of I ₁₅₅₀ ), that is, by changing the threshold value of the amount of water for each pixel determined to be contained in the leaf, the outer shape of the leaf can be correctly determined. it can. Therefore, if the outer shape of the leaf is correctly determined, the average value for each pixel can be calculated accurately. On the other hand, when a fixed area of a spot or the outer shape of a visible light image is used, if the outer shape of the leaf is not correctly captured, a large error will occur in the average value of each pixel.

Here, a comparative example of another method for measuring the water content in the leaves is shown. FIG. 10 is a diagram illustrating an example of a measurement method of a comparative example. The leaf PT3 of the large leaf sealed and packaged in the vinyl bag fk is taken out and fixed to the whiteboard wb so that the leaf PT3 does not move. A whiteboard wb on which the leaf PT3 is firmly fixed is placed on a weigh scale gm, and the weight thereof is measured. At this time, since the weight of the whiteboard wb is measured in advance and adjusted to 0 point, the weight of the leaf is displayed on the meter of the weigh scale gm. The change in weight due to leaf transpiration is measured over time. After completing all measurements, the leaves are completely withered and their weight is determined. By subtracting the weight of the depleted leaf from the weight of the leaf at the time of measurement, the average water content of the leaf at the time of measurement is obtained. The average moisture content of the leaves gradually decreases over time.

On the other hand, in the present embodiment, when measuring the water content of a leaf, a background object is arranged so as to cover the back surface (back side) of the leaf to be measured. Examples of the material of the background material include those that do not contain water and are not deformed by pesticides, watering, or CO2 spraying, such as plastic, coated paper, sheets such as aluminum foil (board), boards, or blocks. In addition, the size of the background object should have a large surface that covers the leaf to be measured, should be within twice the projected area of the leaf to be measured, and should not interfere with the photosynthesis of other leaves. Is desirable. The thickness of the background object is 50 μm to 1 mm, which is self-supporting and does not curl, and is particularly preferably 50 to 200 μm. In addition, the weight of the background material is preferably such that the leaves are supported by the stems of the leaves and the leaves do not wither. The color of the background object is preferably white or silver, which has high reflectance of visible light and near-infrared light.

In this embodiment, a case where a white background plate is used as a background object is shown. Examples of the white background plate include a white plastic plate, an aluminum plate, a standard white plate, and white paper.

FIG. 11A is a graph showing an example of the intensity of reflected light with respect to the wavelength of near-infrared light when the leaves are irradiated with near-infrared light outdoors. The vertical axis shows the intensity of near-infrared light detected by the invisible light sensor NVSS, and the horizontal axis shows the wavelength in the near-infrared region. The intensity of near-infrared light detected by the invisible light sensor NVSS includes the intensity of light by sunlight and the intensity of light scattered by surrounding leaves. In other words, the detected intensity of near-infrared light includes the increase in background due to multiple scattering of sunlight by the surrounding leaves. In addition, the peripheral leaves absorb near-infrared light having a wavelength of 1550 nm, so that the intensity of light detected by the invisible light sensor NVSS is reduced. Therefore, the value of the reflection intensity ratio Ln (I ₉₀₅ / I ₁₅₅₀ ) becomes large. Therefore, when measuring the water content of leaves outdoors, it is necessary to set a large value of the threshold value Sh to be compared with the reflection intensity ratio Ln (I ₉₀₅ / I ₁₅₅₀ ).

FIG. 11B is a graph showing an example of the intensity of the reflected light with respect to the wavelength of the near-infrared light when the leaf on which the white background plate bd is installed is irradiated with the near-infrared light indoors and outdoors. .. The vertical axis shows the intensity of near-infrared light detected by the invisible light sensor NVSS, and the horizontal axis shows the wavelength in the near-infrared region. Since the white background plate bd is arranged so as to cover the back surface (back side) of the leaf PT3t to be measured, multiple scattering from the surrounding leaf PT3o does not occur. Therefore, the intensity of near-infrared light having a wavelength of 1550 nm does not decrease. Also, when indoors, the background does not rise. When measuring outdoors, the threshold value Sh is set to about 0.5. Further, when measuring indoors, the threshold value Sh is set to about 0.3.

When the white background plate bd is arranged on the back surface of the leaf PT3t to be measured, the leaves may be arranged without being fixed, or the leaves PT3t may be attached and fixed to the white background plate bd. Here, a case where the leaf PT3t is attached to the white background plate bd is shown. In each embodiment including the present embodiment, when viewed from the first projection light source 13 and the second projection light source 15 of the plant detection camera 1, the back surface of at least one leaf to be measured has a white background plate bd. Are arranged respectively.

FIG. 12 is an explanatory view of an example of how to attach the leaf PT3t to the white background plate bd. The white background plate bd is a white plastic plate having a vertically long rectangle. An opening bd1 hollowed out in a rectangular shape is formed in the central portion of the white background plate bd. Further, a circular hole portion bd2 is formed on the upper portion of the white background plate bd. A slit bd21 that reaches the upper end surface is formed in the hole bd2. Further, three slits bd3, bd4, and bd5 are formed on the lower side and both sides of the opening bd1 formed in the white background plate bd, respectively.

When the leaf PT3t is attached to the white background plate bd, the tip of the leaf PT3t is inserted into one of the three slits bd3, and the left and right white background plates bd are shifted in the front-rear direction around the slit bd21 to create a gap. The stem PT2 is fixed to the hole bd2 through the leaf stem PT2 inside.

Next, as an observation of the amount of water contained in the leaves of the plant PT using the plant detection camera 1 of the present embodiment, a control experiment of the water potential contained in the leaves was performed, and the resulting water stress in the leaves was obtained. Consider the sugar content of.

FIG. 13 is a graph showing an example of the time change of the standardized pixel average moisture index Dw in the first water potential control experiment. The vertical axis of this graph represents the standardized pixel average moisture index. The standardized pixel average moisture index represents the water potential as an index of the amount of water contained in the leaf to be measured, and is 1 in the invisible light image for the leaf of the plant (that is, the detection result image output from the display processing unit 29). It shows the average amount of water in the leaves contained per pixel. The horizontal axis of the graph represents the elapsed time in days. The target range Bd as an example of the target water content range represents, for example, the target water content range that is judged to be suitable for increasing the sugar content of tomato fruits, and here, the standardized pixel average water content index. The value corresponding to Dw is set in the range of 0.8 to 0.9. This target range Bd differs depending on the type of plant, and even if it is the same plant, its observation location (leaves, stems, etc.). Further, in FIG. 13 and FIG. 14 described later, when the standardized pixel average moisture index Dw is less than the target range Bd, the plant is feeling water stress.

The first water potential control experiment shown in FIG. 13 shows an example of the time-series transition of the standardized pixel average water index when irrigation with an almost appropriate amount of irrigation is performed at the time of irrigation timing. In FIG. 13, the starting point is a state in which the leaves of the plant sample sm1 are wilted, and the water potential control experiment is started after recovery by normal irrigation. In normal irrigation, irrigation was performed regularly twice a day, morning and evening. On the other hand, in the water potential control experiment, irrigation is performed only at the timing determined to be appropriate based on the value of the standardized pixel average moisture index Dw, and regular irrigation is not performed. The experimental results shown in FIG. 13 will be described below. The monitor 50 displays the transition of the standardized pixel average moisture index Dw shown in FIG. 13 over time.

The standardized pixel average water index Dw of the leaves starts from the state of wilting close to the value of 0.60, and normal irrigation is started (day 0). The next day after the start of normal irrigation, the leaf standardized pixel average moisture index Dw recovered to a value of around 1.0. Then, for about a week, normal irrigation was carried out regularly so that the standardized pixel average moisture index Dw of the leaves remained around 1.0 (days 1 to 8). The water was cut off for the next 3 days (9th, 10th, and 11th days). As a result of the water outage, the standardized pixel average moisture index Dw of the leaves gradually decreased until it reached a value of around 0.7 (day 12).

At this point, as shown by arrow r11, when a certain amount of irrigation is performed, the standardized pixel average water index Dw in the leaves rises, and the peak is once included in the target range Bw, but then becomes unirrigated. It descends based on it and deviates from the target range Bw. When the same constant amount of irrigation is performed again at the timing indicated by arrow r12, the standardized pixel average moisture index Dw in the leaves rises again, and after its peak enters the target range Bw, it falls based on non-irrigation. .. At this time, the standardized pixel average moisture index Dw is below the target range Bw, but the amount of deviation is smaller than the previous time. When the same constant amount of irrigation is performed again at the timing indicated by arrow r13, the peak of the standardized pixel average water content index Dw falls after exceeding the upper limit of the target range Bw, but this time the standardized pixel average water content index Dw is the target. It does not fall below the range Bw. Further, when the same constant amount of irrigation is performed at the timing indicated by the arrow r14, the peak of the standardized pixel average moisture index Dw falls after exceeding the upper limit of the target range Bw, but the standardized pixel average moisture index Dw is almost the target. Stay in range Bw (12th to 16th days).

Even if there was a water outage for the next two days (17th and 18th days), as shown by arrows r15, r16, r17, r18, the same irrigation was performed, and the standardized pixel average water content index in the leaves Dw was controlled so as to be substantially within the target range Bw.

FIG. 14 is a graph showing an example of the time change of the standardized pixel average moisture index Dw in the second water potential control experiment. The vertical axis of this graph represents the standardized pixel average moisture index Dw as in FIG. The horizontal axis of the graph represents the elapsed time in minutes. In the second water potential control experiment, two plant samples sm2 and sm3 (for example, tomato) of the same species different from the first plant sample sm1 were used. The plant sample sm2 (comparative example) is regularly irrigated twice in the morning and in the evening. On the other hand, the plant sample sm3 (example corresponding to the present embodiment) is irrigated while applying water stress based on non-irrigation. That is, the plant sample sm3 is not irrigated except at the timing when irrigation is performed, as in the water potential control period (12th to 22nd days) shown in FIG.

In the second water potential control experiment, as shown in FIG. 14, the leaves were divided into four periods: a water potential drop period TW1, an optimum irrigation amount search period TW2, a water stress control period TW3, and a water content recovery period TW4. The standardized pixel average moisture index Dw in the medium was observed. The target range Bw of the standardized pixel average moisture index Dw was set to a value of 0.70 to 0.80, unlike the target range Bw shown in FIG. This is due to the different plant samples used in the second water potential control experiment.

The initial values of the water content in the leaves of Comparative Examples and Examples are 90.5% and 91.2%, respectively, which are almost the same. Further, these standardized pixel average moisture indexes Dw are almost the same around the value of 1.30. Further, the Brix value representing the sugar content of each of the comparative example and the example is the same as the value of 2.3%.

During the period of the water potential control experiment, normal irrigation was continuously performed on the comparative plant sample sm2.

On the other hand, in the water potential drop period TW1 (a period of about 0 to 11520 minutes) with respect to the plant sample sm3 of the example, the plant sample sm3 of the example was not irrigated at all. As a result, after the initial value was set, the standardized pixel average moisture index Dw in the leaves of the comparative example was around 1.0 and was almost constant, whereas the standardized pixel average moisture index in the leaves of the example was almost constant. Dw gradually decreased, and at the end of the water potential drop period TW1, it fell below the lower limit of the target range Bw, which is 0.70.

In the optimum irrigation amount search period TW2 (period around 11520 to 20160 minutes), the standardized pixel average moisture index Dw in the leaves of the example first fell below the lower limit of 0.70 in the target range, and thus the arrow in the figure. At the time point (timing) shown in r1, irrigation with an irrigation amount of K1 was performed. As a result, the standardized pixel average moisture index Dw in the leaves of the examples sharply increased, exceeded the upper limit of the target range Bw, and approached the value of 1.00. At this point, it is determined that the irrigation amount K1 was too large. After that, the water outage period started, and the standardized pixel average moisture index Dw in the leaves of the examples fell below the lower limit of the target range again and reached a value of 0.60. At the end of the water outage period, irrigation with an irrigation amount of K2 was performed at the time indicated by arrow r2. As a result, the standardized pixel average moisture index Dw rises and slightly exceeds the target range Bw. Based on these results displayed on the monitor 50, it is possible to determine that the optimum irrigation amount is less than the irrigation amounts K1 and K2.

In the water stress control period TW3 (a period of about 20160 to 25920 minutes), when the standardized pixel average moisture index Dw in the leaves of the examples starts to decrease again and falls below the lower limit of the target range Bw, irrigation is performed at the time indicated by arrow r3. Irrigation was performed with an irrigation amount K3 less than the amounts K1 and K2. Further, when the standardized pixel average moisture index Dw was below the lower limit of the target range Bw and indicated by the arrow r4, irrigation was performed with the irrigation amount K4 as in the irrigation amount K3. By intermittently irrigating the plant samples K3 and K4 in this way, the standardized pixel average moisture index Dw changes so as to be almost within the target range Bw while applying water stress to the plant sample sm3. To do. After that, since the leaves of the plant sample sm3 of the example entered into a certain water outage period, the degree of wilting of the leaves increased, the standardized pixel average moisture index Dw decreased, and the standardized pixel average moisture of the plant sample sm3. The index Dw has dropped to a value of 0.4.

When the water outage period was completed and the water content recovery period TW4 (a period of about 25920 to 34560 minutes), the degree of wilting of the leaves of the plant sample sm3 was large, so the irrigation amount K3 at the time indicated by arrows r5 and r6, respectively. Irrigation was performed with irrigation amounts K5 and K6 higher than K4.

Moisture content recovery period At the end of TW4, when the water content of the leaves of plant samples sm2 and sm3 in Comparative Examples and Examples became almost the same as the initial values (90.7%, 89.0%). As a result of measuring the Brix value representing each sugar content, the Brix value was 2.8% in the comparative example, whereas the Brix value was 3.3% in the example. That is, the Brix value of the comparative example increased by 0.5% from the value of 2.3% to 2.8% before and after the water potential control, but the Brix value of the example was the value of 2. It increased from 3.3% to 3.3% and increased significantly to 1%.

In this way, compared with the plant sample sm2 of the comparative example in which the irrigation amount was regularly irrigated without applying water stress, in the plant sample sm3 of the example, the standardized pixel average while applying water stress based on non-irrigation. By irrigation at the timing when the water index Dw reached the lower limit of the target range, the amount of increase in the sugar content in the leaves increased, and the increase in the sugar content in the leaves due to water stress was observed. As described above, it was found by the water potential control experiment of FIG. 14 that the quality of leaves was improved by applying water stress.

Here, the sugar content in the leaves was measured by the following procedures (T1) to (T5).

(T1) Leaves of tomatoes and the like are dried at a temperature of 105 ° C. for 2 hours. The water content can be calculated from this weight change.
(T2) Put the dried leaves in a mortar and grind the leaves into powder and grind them.
(T3) Put the crushed leaf powder in a container containing hot water at 60 ° C., which has four times the water content (before drying) contained in the leaves, and stir at room temperature for 2 hours.
(T4) The container containing the leaf powder is left to stand, and the leaf powder is allowed to settle naturally for more than 15 hours.
(T5) Extract the supernatant and measure its Brix value with a sugar content meter. However, since this Brix value is a provisional Brix value obtained by using hot water four times the amount of water in the leaves, a true Brix value can be obtained according to the mathematical formula (1). The calculation of the true Brix value by the mathematical formula (1) may be performed by the control unit 11 when the Brix value obtained by the sugar content meter is input.

True Brix value (%) = [Temporary Brix value x Moisture content x 4 times / (1-Temporary Brix value)] ÷ [Water content + (Temporary Brix value x Moisture content x 4 times) / (1- Temporary Brix value)] x 100
…… (1)

Based on the above water potential control experiment, the following irrigation amount and irrigation timing are considered. FIG. 15 is a graph illustrating an example of irrigation amount and irrigation timing. The vertical axis of this graph represents the standardized moisture index (that is, the standardized pixel average moisture index Dw). The horizontal axis represents the elapsed time. In the graph, the measurement points are represented by rectangles. The target range Bw is set to a value of 0.8 to 0.9.

The initial value of the standardized pixel average moisture index Dw in the leaf is 1.0. When the standardized pixel average moisture index Dw gradually decreases from the initial value with the passage of time and reaches the vicinity of the lower limit of the target range Bw, the next irrigation is performed. When the slope (descent speed) at which the standardized pixel average moisture index Dw decreases is "-a", the timing indicated by the arrow ra at which the standardized pixel average moisture index Dw crosses the lower limit of the target range Bw becomes the irrigation point tp. ..

The irrigation amount Kp at the irrigation point tp can be obtained by using, for example, the mathematical formula (2).

Moisture content in the next leaf = Moisture content in the leaf this time + Water absorption from the root-Evapotranspiration from the leaf …… (2)

Here, the amount of water absorbed from the roots can be obtained from the amount of irrigation, the osmotic pressure of liquid fertilizer (electrical conductivity), the number of roots (surface area), and the like. The amount of transpiration from leaves can be obtained from the number of leaves, leaf area, saturation (that is, the difference between saturated water vapor pressure and relative humidity) and the like. In general, leaf photosynthesis is active and transpiration is active on sunny days with a saturation difference of ³ to 7 g / m ³ (that is, a period when the relative humidity is around 75% RH). Is said to be. Therefore, the amount of water in the leaves tends to decrease in the morning and noon on a sunny day due to the active transpiration, but on the other hand, when the amount of transpiration of the leaves decreases in the evening (sunset), the amount of water in the leaves increases. To do. In addition, since the leaves do not photosynthesize at night, the change in water content in the leaves is small. In addition, on rainy days, the relative humidity is high and transpiration does not occur even if the stomata are opened, so the change in water content in the leaves is small, and on hot days such as summer, the plant loses more water in the body. Since the stomata are closed so as not to occur, transpiration does not occur and the change in water content in the leaves becomes small.

When irrigation is performed, the standardized pixel average moisture index Dw rises, reaches the upper limit of the target range Bw, and then repeats the operation of falling again. At the timing indicated by the arrow rb, irrigation similar to the timing indicated by the arrow ra is performed. After that, at the timing indicated by the arrow rc, irrigation is performed at the timing when the lower limit value of the target range Bw is exceeded and the standardized pixel average moisture index Dw reaches the value 0.7, that is, when the water stress is increased. This can give water stress to the plants.

FIG. 16 is a flowchart illustrating an example of the optimum irrigation amount search procedure in the first embodiment. This optimum irrigation amount search operation is a process executed in the optimum irrigation amount search period TW2 shown in FIG. 14, and is executed, for example, when the irrigation amount search mode button 71 is pressed on the UI screen 60 shown in FIG. To.

In the optimum irrigation amount search operation, first, the control unit 11 sets the initial value, the upper limit value and the lower limit value of the target range Bw by the operation of the user (for example, the farmer who is the tomato grower) on the UI screen 60 (S41). ). The control unit 11 displays the predicted descent time to the lower limit of the target range Bw and the scheduled search irrigation time (S42). The scheduled search irrigation time is set to the same time as or near the predicted descent time.

The control unit 11 displays the search irrigation amount input screen 61 shown in FIG. 18 (S43). The control unit 11 determines whether or not the input of the search irrigation amount is completed (S44), and if the input is not completed, continues to display the search irrigation amount input screen 61 in step S43.

Further, when the input of the search irrigation amount is completed, the control unit 11 measures the standardized pixel average moisture index Dw and adds this measurement point to the graph in the leaf moisture monitoring screen Gm1 displayed on the UI screen 60. (S45). The control unit 11 determines whether or not the scheduled search irrigation time has come (S46). If the scheduled search irrigation time has not arrived, the control unit 11 returns to the process of step S45.

At the scheduled search irrigation time, the control unit 11 controls the dropping of water in the search irrigation amount (S47). This search irrigation amount corresponds to the irrigation amounts K1 and K2 in FIG. Further, the dropping of water in the search irrigation amount may be performed automatically by the fertilizer water supply device WF, or may be performed manually by a person. The control unit 11 calculates the moisture index after waiting until the designated time (S48). This designated time is a time designated so that the standardized pixel average moisture index Dw reaches the upper limit of the target range Bw, and is set based on the predicted descent time and the scheduled search irrigation time.

The control unit 11 compares the standardized pixel average moisture index Dw with the upper limit of the target range Bw (S49). When the standardized pixel average moisture index Dw exceeds the upper limit of the target range Bw, the control unit 11 returns to step S42 and displays the predicted descent time and the search irrigation scheduled time again on the UI screen 60. If the standardized pixel average moisture index Dw does not exceed the upper limit of the target range Bw, the control unit 11 returns to step S43 and displays the search irrigation amount input screen 61.

Further, when the standardized pixel average water content index Dw becomes equal to the upper limit value of the target range Bw, the control unit 11 displays the search irrigation amount as the optimum water amount to shift to the cultivation control process (S50). This display is popped up, for example, in a message or the like. After this, the control unit 11 ends this operation.

FIG. 17 is a diagram showing an example of a user interface (UI) screen 60 relating to water potential control. The UI screen 60 includes a leaf moisture monitoring screen Gm1. On the leaf moisture monitoring screen Gm1 arranged at the upper part of the UI screen 60, a graph showing the time-series change of the standardized pixel average moisture index Dw is displayed. This graph is similar to the graph of FIG. 13 described above.

The setting area 63 is displayed on the left side of the lower part of the UI screen 60. An initial setting button 64 and a deviation threshold setting button 66 are arranged in the setting area 63. Further, an input box 67 for setting the upper limit value of the target range Bw and an input box 68 for inputting the lower limit value of the target range Bw are arranged. A touch panel, a numeric keypad, a mobile terminal, or the like can be used to input numerical values to the input boxes 67 and 68.

Further, a water stress control (cultivation control) mode button 73 is arranged on the lower right side of the lower part of the UI screen 60. When the irrigation amount search mode button 71 is pressed, the optimum irrigation amount search operation shown in FIG. 16 described above starts. When the water stress control (cultivation control) mode button 73 is pressed, the cultivation control operation shown in FIG. 19 to be described later starts. Further, on the UI screen 60, a display box 72 for displaying the set value of the search irrigation amount and a display box 74 for displaying the set value of the cultivated irrigation amount are arranged.

FIG. 18 is a diagram showing an example of the search irrigation amount input screen 61 popped up on the UI screen 60. On the search irrigation amount input screen 61, the search irrigation amount is input and set in units of milliliters (ml). A touch panel, a numeric keypad, a mobile terminal, or the like can be used to input the search irrigation amount.

FIG. 19 is a flowchart illustrating an example of the water stress control (cultivation control) procedure of the first embodiment. This cultivation control operation is a process executed in the water stress control period TW3 shown in FIG. 14, for example, when the water stress control (cultivation control) mode button 73 is pressed on the UI screen 60 shown in FIG. Will be done.

In the water stress control operation, the control unit 11 first displays a cultivation (control) irrigation amount input screen (not shown) (S61). This cultivation irrigation amount input screen is pop-up-displayed on the UI screen 60 like the search irrigation amount input screen.

On the cultivation irrigation amount input screen, the control unit 11 determines whether or not the input of the cultivation irrigation amount is completed (S62). The cultivated irrigation amount indicates an appropriate irrigation amount obtained in the search process of the optimum irrigation amount search period TW2 (that is, the flowchart shown in FIG. 16). When the input of the cultivation irrigation amount is not completed, the control unit 11 returns to step S61 and continues to display the cultivation irrigation amount input screen.

On the other hand, when the input of the cultivation irrigation amount is completed, the control unit 11 drops the water of the cultivation irrigation amount (S63). The control unit 11 displays the predicted descent time to the lower limit of the target range Bw and the scheduled cultivation irrigation time (S64). The scheduled cultivation irrigation time is set to the same time as or near the predicted descent time.

The control unit 11 determines whether or not to change the cultivation irrigation amount (S65). When the cultivation irrigation amount is not changed, the control unit 11 proceeds to the process of step S68. On the other hand, when the cultivation irrigation amount is changed, the control unit 11 displays the cultivation irrigation amount input screen again (S66). On the cultivation irrigation amount input screen, the control unit 11 determines whether or not the input of the cultivation irrigation amount is completed (S67). If the input of the cultivation irrigation amount is not completed, the control unit 11 returns to step S66 and continues to display the cultivation irrigation amount input screen.

On the other hand, when the input of the cultivation irrigation amount is completed, the control unit 11 determines whether or not the scheduled cultivation irrigation time has come (S68). If the scheduled cultivation irrigation time has not arrived, the control unit 11 returns to the process of step S64. At the scheduled cultivation irrigation time, the control unit 11 drops the amount of water in the cultivation irrigation amount (S69). The control unit 11 determines whether or not to end the cultivation control (S30). When the cultivation control is not finished, the control unit 11 returns to the process of step S64. On the other hand, when the cultivation control is terminated, the control unit 11 ends this operation.

Next, a water stress profile for applying water stress to plants will be described. 20 (A) to 20 (D) are diagrams schematically showing an example of a water stress profile. In the water stress profile pf1 shown in FIG. 20 (A), the water content index (that is, the standardized pixel average water content index Dw; the same applies hereinafter) between the upper limit value and the lower limit value of the target range Bw (the range of the water content of the target). Irrigation is performed so that That is, at the timing of the lower limit value of the target range Bw, the irrigation amount is irrigated so as to reach the upper limit value of the target range Bw. In this case, the water stress is small.

In the water stress profile pf2 shown in FIG. 20 (B), irrigation is performed at the lower limit of the target range Bw, the peak of the standardized pixel average moisture index Dw falls in the middle of the target range Bw, and the standardized pixel average moisture index Dw Try to reduce fluctuations. In this case, the water stress is fairly small.

In the water stress profile pf3 shown in FIG. 20 (C), after the standardized pixel average water index Dw is lowered to the atrophy point, irrigation is performed with a large amount of irrigation until the standardized pixel average water index Dw exceeds the value 1. After raising it, it is lowered again to the atrophy point, and irrigation is performed in the same manner. In this case, there is no water stress in the region where the standardized pixel average moisture index Dw exceeds the value 1, and the water stress is large in the vicinity of the wilting point. This water stress profile pf3 is used, for example, when the water index changes at the time of flowering or fruiting of plants in other stages, or when it changes depending on the weather.

In the water stress profile pf4 shown in FIG. 20 (D), after lowering the standardized pixel average water index Dw to the atrophy point, irrigation is performed with an irrigation amount that reaches the upper limit of the target range Bw, and the standardized pixel average water content is reached. When the index Dw reaches the upper limit of the target range Bw and then reaches the lower limit of the target range Bw again, irrigation is performed with an irrigation amount that reaches the upper limit of the target range Bw. Such operations are repeated alternately. In this case, when the standardized pixel average moisture index Dw is near the wilting point, the water stress is large, but when it is near the lower limit of the target range Bw, the water stress is small. Note that these water stress profiles are examples, and other water stress profiles can be applied.

As described above, in the plant detection camera 1 of the first embodiment, the first projection light source 13 of the plant detection camera 1 has a characteristic of being hard to be absorbed by water by optical scanning, and is near-infrared light having a first wavelength (905 nm). (Reference light) is irradiated toward the leaf PT3 of the plant PT. The second projection light source 15 of the plant detection camera 1 irradiates the leaf PT3 of the plant PT with near-infrared light (measurement light) having a second wavelength (1550 nm) having a characteristic of being easily absorbed by water by optical scanning. .. The threshold setting / moisture index detection processing unit 27a is based on the reflected light of 905 nm reflected at all irradiation positions of the leaf PT3 and the reflected light of 1550 nm reflected at all irradiation positions of the leaf PT3, and the sum of the reflection intensity ratios is ΣLn ( The total water content of one leaf, which is I ₉₀₅ / I ₁₅₅₀ ), and the pixel average water content index are calculated. The control unit 11 displays a graph showing the time-series transition of the amount of water contained in the leaf PT3 of the plant PT from the start to the end of the measurement period on the UI screen 60 of the monitor 50. A white background plate bd (background object) covering the back surface of the leaf PT3 of the plant PT is arranged on the leaf PT3 of the plant PT when viewed from the first projection light source 13 and the second projection light source 15.

In this way, according to the plant detection camera 1, by displaying a graph showing the time-series transition of the water content contained in the leaf PT3 of the plant PT on the UI screen 60 of the monitor 50, the water content contained in the plant can be measured. The transition can be presented quantitatively and in chronological order. Further, according to the time-series transition of the standardized pixel average moisture index Dw contained in the leaf PT3 displayed on the UI screen 60 of the monitor 50, the plant detection camera 1 informs the user about the timing of irrigation of the leaf PT3 and the irrigation. It is also possible to teach the quantity. The user can irrigate an appropriate amount of irrigation at an appropriate irrigation timing from the graph displayed on the UI screen 60 of the monitor 50. Therefore, when improving the functionality of plants such as tomatoes, it is possible to perform optimum cultivation control, improve the yield, and increase the productivity.

Further, according to the plant detection camera 1, the target range Bw of the standardized pixel average moisture index Dw (moisture content) of the plant, the initial value of the water content, and unirrigated water as an example of applying stress (for example, water stress). Since the change in the amount of water that is falling is displayed, the user can grasp the amount of water in the plant in chronological order.

Further, according to the plant detection camera 1, it is possible to search for the optimum irrigation amount such that the standardized pixel average water content index Dw (water content) of the plant falls within the target range Bw.

Further, according to the plant detection camera 1, both the decrease in the water content due to unirrigation and the increase in the water content due to irrigation are displayed as an example of applying stress (for example, water stress), so that the standardized pixel average water content is displayed. It becomes easier to search for the optimum amount of irrigation such that the index Dw falls within the target range Bw.

Further, according to the plant detection camera 1, the target range Bw of the water content of the plant and the change of the water content due to irrigation to keep the water content of the plant in the target range are displayed, so that the water content of the plant is It becomes easier to irrigate the amount of irrigation that falls within the target range.

Further, according to the plant detection camera 1, it is possible to compare the amount of water contained in the plant irrigated by normal irrigation with the amount of water contained in the plant irrigated while applying water stress. Therefore, the user can efficiently and accurately judge the suitability of the irrigation amount and the irrigation timing.

(Modification 1 of the first embodiment)
FIG. 21 is a flowchart illustrating an example of the optimum irrigation amount search procedure in the first modification of the first embodiment. The same step processing as in FIG. 16 will be omitted by assigning the same step number. After waiting until the designated time in step S48, the control unit 11 calculates the moisture index, and then increases the search irrigation amount and the standardized pixel average moisture index Dw so that the moisture index is maintained within the target range Bw (within the range). Is displayed (S49A). Based on these displays, the user can estimate the optimum amount of water. After this, the control unit 11 ends this operation.

(Second Embodiment)
The second embodiment shows a case where the leaf position shifts due to some influence while continuously measuring the standardized pixel average moisture index Dw in the leaf. When the standardized pixel average moisture index Dw in a leaf is being measured in chronological order, for example, when the white background plate to which the leaf to be measured is attached tilts due to strong wind or collision and the leaf position shifts, it is caused by irradiation with laser light. The standardized pixel average moisture index Dw in the leaf measured by the reflection intensity ratio will change abruptly.

When the position of the leaf to be measured shifts, the data recording the standardized pixel average moisture index Dw in the leaf in time series fluctuates at once and the continuity is lost. The data of the standardized pixel average moisture index Dw measured in 1 was discarded, and the measurement was restarted from the beginning. As a result, the acquisition efficiency of measurement data was significantly reduced.

In the second embodiment, even if the leaf position shifts, the data of the standardized pixel average moisture index Dw in the leaf can be efficiently utilized by effectively utilizing the data measured in the time series so far without discarding it. It can be obtained well and the increase in measurement time should be suppressed.

FIG. 22A is a diagram showing an image showing the water content of the leaf to be measured, which is captured by the plant detection camera 1 of the second embodiment, and shows an example of an image of the leaf before the misalignment. .. FIG. 22B is a diagram showing an image showing the water content of the leaf to be measured, which is captured by the plant detection camera 1 of the second embodiment, and shows an example of an image of the leaf after misalignment. .. In the figure, the region where the number of dots is large and dark is the region where the water content is high. The darkest (highest water content) region sc1 is located inside the leaves. The next darkest region (slightly higher water content) region sc2 exists around the region sc1. The thin region (low water content) region sc3 exists on the outside of the leaf. In addition, the area of the region sc1 having a large water content increases after the displacement as compared with before the displacement.

FIG. 23 is a graph showing an example of the time change of the standardized pixel average moisture index Dw in the water potential control experiment when the positional deviation occurs. The vertical axis of this graph represents the standardized pixel average moisture index as in the first embodiment. The standardized pixel average water content index represents the water potential, and indicates a value corresponding to the amount of water contained in one pixel in an image obtained by imaging a plant leaf. The horizontal axis of the graph represents the elapsed time in minutes.

When the leaves are misaligned (see timing tk in the figure), the standardized pixel average moisture index Dw changes at once. The standardized pixel average moisture index Dw in the leaf when there is no misalignment of the leaf changes as shown in the graph gh1. On the other hand, the standardized pixel average moisture index Dw in the leaves when the leaves are misaligned changes as shown in the graph gh2.

In the second embodiment, even if there is a leaf misalignment, the data of the standardized pixel average moisture index Dw before the leaf misalignment is effectively utilized by making corrections based on the following considerations. The data of the standardized pixel average moisture index Dw in time series is acquired so as to maintain continuity with the data of the standardized pixel average moisture index Dw after the leaf position shift.

In the following discussion, it is assumed that the leaves are tilted as the position of the leaves. In this case, tilting the leaf in the pan direction or the tilt direction and changing the angle corresponds to a change in the thickness of the leaf when viewed from the camera.

The water content in the leaf (in other words, the water potential), which is the amount of water contained in the leaf, is proportional to the standardized pixel average water index Dw. Further, as described above, the standardized pixel average moisture index Dw constitutes the sum of the reflection intensity ratio Ln (I ₉₀₅ / I ₁₅₅₀ ) and the number of pixels constituting the invisible light image of the leaf or the visible light captured image of the leaf. It is obtained from the number of pixels that occupy green (G) among the number of pixels.

It is known that the reflection intensity ratio Ln (I ₉₀₅ / I ₁₅₅₀ ) is almost proportional (correlated) with the leaf thickness t as shown in the mathematical formula (3) based on the known Lambert-Beer law. .. In mathematical formula (3), α: water absorption coefficient, t: leaf thickness, C: water concentration, β: scattering loss term.

Ln (I ₉₀₅ / I ₁₅₅₀ ) = α ・ t ・ C + β …… (3)

In summary, the water content (water potential) in the leaves is represented by a linear function of the standardized pixel average moisture index Dw, which has the leaf thickness t as a gradient (slope). That is, the slope of the water content in the leaf changes depending on the thickness t of the leaf.

As described above, the change in the leaf angle due to the positional shift corresponds to the change in the inclination due to the leaf thickness t, and therefore corresponds to the change in the leaf angle (change in the inclination due to the leaf thickness t). By multiplying the data of the standardized pixel average moisture index Dw after the misalignment by the coefficient Q (correction coefficient) to be performed, the data of the standardized pixel average moisture index Dw before the misalignment can be obtained.

As a result, the data of the standardized pixel average moisture index Dw obtained in time series before and after the positional deviation can maintain continuity. However, since the water content immediately before and immediately after the position shift is acquired within a short time, the actual water content does not change between them.

Specifically, a correction example of the standardized pixel average moisture index Dw before and after the positional deviation is shown. FIG. 24 is a table showing an example of the standardized pixel average moisture index before and after the misalignment correction in chronological order. In this table, in the graph shown in FIG. 23, when the elapsed time is 16250 minutes (time 17:10) and the position shift occurs, the standardized pixel average moisture index Dw before correction and the standardized pixel average moisture index Dw after correction are displayed. It is shown. Here, the coefficient Q corresponding to the change in the leaf angle is calculated by the control unit 11 as an example of the coefficient calculation unit, and specifically, the value is 0.7303 (= 0.6416 / 0.8785). ..

FIG. 25 is a flowchart illustrating an example of the position deviation correction procedure in the second embodiment. The plant detection camera 1 of the second embodiment has substantially the same configuration as that of the first embodiment. The same components as those in the first embodiment are used with the same reference numerals, and the description thereof will be omitted.

The control unit 11 acquires the standardized pixel average moisture index Dw1 at the current time and displays it on the UI screen 60 (S91). The control unit 11 acquires and displays the standardized pixel average moisture index Dw2 after the specified elapsed time (for example, after 30 minutes) (S92). The specified elapsed time corresponds to the measurement interval.

The control unit 11 determines whether or not the difference between the standardized pixel average moisture index Dw1 and the standardized pixel average moisture index Dw2 exceeds the threshold value th (S93). This threshold value th is used to determine a value at which it is assumed that the leaf position shift occurs and the standardized pixel average moisture index Dw changes.

Here, the threshold value th is set in advance. When setting the threshold value th, the control unit 11 displays a deviation determination threshold input screen (not shown). The user inputs the threshold value th for determining that the positional deviation has occurred on the deviation determination threshold input screen. When the input is completed, the control unit 11 displays this input value and accepts the setting of the threshold value th.

When the difference between the standardized pixel average moisture index Dw1 and the standardized pixel average moisture index Dw2 does not exceed the threshold value th, that is, when it is assumed that the leaf position shift does not occur, the control unit 11 proceeds to the process of step S95. On the other hand, when the difference between the standardized pixel average moisture index Dw1 and the standardized pixel average moisture index Dw2 exceeds the threshold th, the control unit 11 determines that the positional deviation has occurred, and determines that the positional deviation has occurred, and the standardized pixel average moisture index Dw2 and the standardized pixel average thereafter. The value of the moisture index Dw is displayed on the UI screen 60 after correcting the deviation amount (S94).

After that, the control unit 11 determines whether to end the search control of the optimum irrigation amount, or to end the cultivation control, or not (S95). When the search control of the optimum irrigation amount is not finished and the cultivation control is not finished, the control unit 11 returns to the process of step S91. On the other hand, when the search control of the optimum irrigation amount is terminated or the cultivation control is terminated, the control unit 11 ends this operation.

As described above, in the plant detection camera 1 of the second embodiment, the control unit 11 as an example of the detection unit detects the misalignment of the plant. When the misalignment of the plant is detected, the control unit 11 calculates a coefficient Q (correction coefficient) to be multiplied by the moisture index after the misalignment based on the moisture index before and after the misalignment. The control unit 11 corrects the amount of misalignment by multiplying the coefficient Q by the moisture index after misalignment, and is corrected so that the moisture index before misalignment and the moisture index after misalignment maintain continuity. The result is displayed on the UI screen 60 of the monitor 50.

As a result, the continuity of the standardized pixel average moisture index Dw in the leaves measured in time series can be maintained even when the leaf position shift occurs. Therefore, the standardized pixel average moisture index Dw data in the leaves measured so far can be used meaningfully and effectively without wasting it. As a result, time-series data of the standardized pixel average moisture index Dw in the leaves can be efficiently acquired, and even if the position shift occurs in the middle, the increase in the measurement time of the standardized pixel average moisture index Dw is suppressed. can do.

(Modification 1 of the second embodiment)
In the second embodiment, the leaf position shift is determined by whether or not the difference of the standardized pixel average moisture index Dw exceeds the threshold value th, but the case where the leaf position shift is physically detected is shown.

FIG. 26A is a diagram showing a white background plate bd used for detecting the positional deviation in the first modification of the second embodiment, and is a front view of the white background plate bd. FIG. 26B is a view showing a white background plate bd used for detecting the positional deviation in the first modification of the second embodiment, and is a side view of the white background plate bd shown in FIG. 26A. Is.

A black-painted quadrangular frame bd11 having a shape like a frame is provided on the peripheral edge of the white background plate bd. In addition, marks mk1 to mk4 of the rice mark are drawn at the four corners of the front surface of the white background plate bd, respectively. Further, a leaf PT3 is attached to the center of the surface of the white background plate bd.

When the leaf PT3 attached to the white background plate bd is imaged by the plant detection camera 1, the white background plate bd and the finder of the plant detection camera 1 are parallel to each other by aligning the black-painted frame body bd11 with the frame of the finder. Give a degree. By imaging the white background plate bd in this state, each distance between the marks mk1 to mk4 is compared with a pre-registered reference distance. This reference distance is the distance between the marks mk1 to mk4 imaged when the white background plate bd is set to be parallel to the plant detection camera 1. When each distance between the marks mk1 to mk4 is shorter than the reference distance, it is determined that the white background plate bd is tilted and the position is displaced.

For example, it can be seen that the shorter the distance between the mark mk1 and the mark mk4 is compared with the reference distance, the larger the tilt angle. It can be seen that the shorter the distance between the mark mk1 and the mark mk2 is compared with the reference distance, the larger the pan angle.

In this way, it is possible to physically detect the misalignment of the leaves and measure the amount of the misalignment. Furthermore, by registering the coefficient Q corresponding to the measured amount of misalignment, the standardized pixel average moisture index before and after correction is used when multiplying the data of the standardized pixel average moisture index Dw after the misalignment. It is not necessary to use the Dw data. Therefore, the processing load can be reduced.

(Modification 2 of the second embodiment)
FIG. 27 is a diagram illustrating an example of mechanical arrangement of the white background plate bdd and the plant detection camera 1 in the second modification of the second embodiment. The white background plate bdd is attached on the bar 102 erected on the base 101 and installed as a stand. The plant detection camera 1 is fixed to a tripod 151. Further, the white background plate bdd is mechanically connected to and fixed to the plant detection camera 1 by a connecting member mp such as a wire or a bar. When the white background plate bdd is displaced, the change is directly transmitted to the plant detection camera 1. For example, when a large positional deviation occurs, a large change occurs in the image captured by the plant detection camera 1.

The plant detection camera 1 is positioned on the white background plate bd when the correlation degree of the images captured in time series is below the threshold value, that is, when the similarity between the previous frame image and the current frame image is significantly reduced. It may be determined that a deviation has occurred. As a result, the misalignment of the white background plate bd can be detected relatively easily.

Further, the detection of the positional deviation is not limited to the above method. For example, the plant detection camera 1 may be equipped with an acceleration sensor that detects an impact. When the white background plate bdd is displaced, the change in the white background plate bdd is transmitted to the plant detection camera 1 via the connecting member mp. When the impact is detected by the acceleration sensor mounted on the plant detection camera 1, it may be detected that the white background plate bdd has been displaced.

(Third Embodiment)
In the first embodiment, for example, as shown in FIG. 15, when the leaf PT3 to be observed is irrigated, the standardized pixel average moisture index increases but decreases based on the subsequent non-irrigation. The timing was when the standardized pixel average moisture index decreased to near the lower limit of the target range Bw.

The amount of water in the leaves at the time of the next calculation by the plant detection camera 1 is obtained by adding the amount of water absorbed from the roots to the amount of water in the leaves at the present time and further subtracting the amount of evapotranspiration of the leaves (Formula (2)). reference). Normally, irrigation causes the roots to absorb water, increasing the amount of water in the leaves at the next calculation. However, since the leaves are not irrigated during the time period between the irrigation timing and the next irrigation timing, the amount of transpiration of the leaves during that period varies depending on the environmental conditions (for example, temperature and humidity) around the leaves. However, the plant detection camera 1 of the first embodiment does not consider controlling the amount of transpiration in consideration of the environmental conditions around the leaves.

Therefore, in the third embodiment below, the user considers the environmental conditions around the leaves (for example, temperature and humidity) that determine the amount of transpiration of the leaves, and includes irrigation timing for obtaining high sugar content and high yield. An example of a plant detection camera 1 that instructs to maintain or change the environmental conditions around the leaf PT3 in the greenhouse VGH in order to apply water stress according to the water stress profile according to the preference of the greenhouse will be described. Since the configuration of the plant detection camera 1 of the third embodiment is the same as that of the plant detection camera 1 of the first embodiment, the same description will be omitted and different contents will be described.

FIG. 31 is an explanatory diagram showing an example of the relationship between temperature, relative humidity, and saturation. FIG. 32 is an explanatory diagram showing an example of the transition of leaf transpiration due to changes in temperature and relative humidity. 33 (A) to 33 (D) are diagrams schematically showing each example of a water stress profile based on leaf transpiration due to changes in temperature and relative humidity. In FIGS. 33 (A) to 33 (D), the time-series transition of the standardized pixel average moisture index or the standardized moisture index sum is simply shown.

When the environmental conditions around the leaf PT3 (for example, temperature and humidity) change, the saturation of the leaf PT3 fluctuates as shown in FIG. As a result, the amount of transpiration of leaf PT3 changes. More specifically, when the temperature around the leaf PT3 decreases and the humidity around the leaf PT3 rises, the saturation becomes smaller, and the leaf PT3 opens stomata but does not easily evaporate. Further, when the temperature around the leaf PT3 rises and the humidity around the leaf PT3 rises, the saturation difference becomes large and the transpiration becomes excessive, so that the leaf PT3 closes the stomata so as not to lose water. It is generally said that the photosynthesis of leaf PT3 is active and the suitable saturation difference is 3 to 7 (g / m ³ ), and the range surrounded by the dotted line CU1 and the dotted line CU2 shown in FIG. 32. The temperature and humidity at which the saturation is obtained are preferable as the environmental conditions around the leaf PT3.

(1) A1 state before change in FIG. 32 → A1-state after change in FIG. 32 When this state transition occurs, the temperature rises and the humidity drops, but the saturation is included in the range suitable for photosynthesis of leaf PT3. Therefore, the transpiration of leaf PT3 becomes active. In other words, since the amount of leaf transpiration shown in the formula (2) increases, the slope −a shown in FIG. 15 increases, and the irrigation point is accelerated. Therefore, the plant detection camera 1 increases the inclination −a shown in FIG. 15 by instructing the control device 200 so that the temperature and humidity are such that the saturation in the state of A1- after the change can be obtained, and the irrigation point. Can be accelerated.

(2) A2 state before change in FIG. 32 → A2-state after change in FIG. 32 When this state transition occurs, the temperature drops and the humidity rises, but the saturation is included in the range suitable for photosynthesis of leaf PT3. Therefore, the transpiration of leaf PT3 becomes active. In other words, since the amount of leaf transpiration shown in the formula (2) increases, the slope −a shown in FIG. 15 increases, and the irrigation point is accelerated. Therefore, the plant detection camera 1 increases the inclination −a shown in FIG. 15 by instructing the control device 200 so that the temperature and humidity are such that the saturation in the state of A2- after the change can be obtained, and the irrigation point. Can be accelerated.

(3) A3 state before change in FIG. 32 → A3-state after change in FIG. 32 When this state transition occurs, the temperature drops and the humidity rises, but the transpiration is not included in the range suitable for photosynthesis of leaf PT3. Evaporation of leaf PT3 is reduced. In other words, since the amount of leaf transpiration shown in the formula (2) is reduced, the slope −a shown in FIG. 15 is reduced and the irrigation point is delayed. Therefore, the plant detection camera 1 reduces the inclination −a shown in FIG. 15 by instructing the control device 200 so that the temperature and humidity are such that the saturation in the state of A3- after the change can be obtained, and the irrigation point. Can be delayed.

(4) A4 state before change in FIG. 32 → A4-state after change in FIG. 32 When this state transition occurs, the temperature rises and the humidity drops, but the transpiration is not included in the range suitable for photosynthesis of leaf PT3. Evaporation of leaf PT3 is reduced. In other words, since the amount of leaf transpiration shown in the formula (2) is reduced, the slope −a shown in FIG. 15 is reduced and the irrigation point is delayed. Therefore, the plant detection camera 1 reduces the inclination −a shown in FIG. 15 by instructing the control device 200 so that the temperature and humidity are such that the saturation in the state of A4- after the change can be obtained, and the irrigation point. Can be delayed.

Therefore, as shown in FIG. 33 (A), the plant detection camera 1 can obtain a water stress profile in which the standardized pixel average moisture index or the sum of the standardized moisture indexes is set to a constant value at both the decreasing and increasing slopes. In addition, the control device 200 can be instructed to control the ambient temperature and humidity.

Further, as shown in FIG. 33 (B), the plant detection camera 1 moderates the slope of the standardized pixel average moisture index or the sum of the standardized moisture indexes when decreasing, and increases the slope when increasing in FIG. 33 (A). The control device 200 can be instructed to control the ambient temperature and humidity so as to obtain a water stress profile that is consistent with the slope of time. In this case, since the slope of the standardized pixel average water index or the total standardized water index when decreasing is small, the irrigation timing is longer than the irrigation timing in FIG. 33 (A).

Further, as shown in FIG. 33C, the plant detection camera 1 controls the ambient temperature and humidity so as to obtain a water stress profile that does not increase or decrease the standardized pixel average moisture index or the total standardized moisture index in a certain period. Can be instructed to the control device 200. In this case, since the transpiration of leaf PT3 decreases in a certain period of time, the irrigation timing is longer than the irrigation timing in FIG. 33 (A).

Further, as shown in FIG. 33 (D), the plant detection camera 1 shows the slopes of the standardized pixel average moisture index or the sum of the standardized moisture indexes when decreasing and increasing as shown in FIG. 33 (A). The control device 200 can be instructed to control the ambient temperature and humidity so that a water stress profile having a value larger than the slope of is obtained. In this case, the transpiration of the leaf PT3 becomes active, decreases, and fluctuates violently, so that the irrigation timing is shorter than the irrigation timing in FIG. 33 (A).

FIG. 34 is a diagram showing another example of a user interface (UI) screen relating to water potential control. FIG. 35 is a diagram showing an example of a fixed value setting input screen of the environment control mode 300 designated on the UI screen 60 shown in FIG. 34. FIG. 36 is a diagram showing an example of a saturation setting program input screen of the environment control mode designated on the UI screen 60 shown in FIG. 34.

The difference between the UI screen 60 of FIG. 34 and the UI screen 60 shown in FIG. 17 will be described, and the same reference numerals will be given to the same ones to omit the description. In the UI screen 60 of FIG. 34, a button of the environment control mode 300 for controlling the environmental conditions (for example, temperature and humidity) around the leaf PT3 to be observed is provided. When the button of the environment control mode 300 is pressed by the user's operation, the control unit 11 of the plant detection camera 1 monitors the constant value setting input screen Gm2 shown in FIG. 35 or the saturation setting program input screen shown in FIG. Display at 50.

On the fixed value setting input screen Gm2 shown in FIG. 35, temperature (° C.), humidity (RH%), wind speed (cm / s), and saturation (g / m ³ ) can be obtained so that a constant saturation (g / m ³ ) can be obtained. Each of the input areas of m ³ ) is provided, and an automatic saturation conversion button for automatically calculating the saturation difference is provided. In FIG. 35, for example, 60 cm / s is input so that the wind speed becomes constant. The value of the wind speed can be input, for example, 20 to 180 cm / s depending on the performance of the air conditioner 227.

When the satiety automatic conversion button is pressed after the temperature and humidity are input, the control unit 11 calculates the saturation and displays the value of the calculation result in the saturation input area. When this calculated value or the saturation value desired by the user is input and specified and the start button is pressed, the control unit 11 tells the control device 200 the saturation specified around the leaf PT3 to be observed. Send environmental control instructions to get the value. This environmental control instruction may include only the target saturation value, or may include not only the saturation value but also the temperature and humidity for obtaining the saturation value. When the control device 200 receives the environmental control instruction from the plant detection camera 1, the control device 200 of each device in the vinyl house VGH so that the saturation value or the temperature, humidity and the saturation value included in the environmental control instruction can be obtained. Start control or maintain control.

In the saturation setting program input screen Gm3 shown in FIG. 36, a drawing area for changing the set temperature (° C.) and the set humidity (RH%) with time is provided so that the user can specify an arbitrary saturation. .. Further, as shown in FIG. 36, input regions for a temperature lowering rate (° C./h), a holding time (h), and a temperature rising rate (° C./h) may be provided with respect to the set temperature (° C.). Similarly, with respect to the set humidity (RH%), input regions for the humidification rate (% / h), the holding time (h), and the drying rate (% / h) may be provided.

When the saturation automatic conversion button is pressed after the set temperature and the set humidity are specified for drawing, the control unit 11 calculates the saturation and changes the saturation time with the time change of the set temperature and the set humidity. Display on the screen. After that, when the start button is pressed by the user's operation, the control unit 11 controls the environment for the control device 200 to obtain a time change of the saturation value specified for drawing around the leaf PT3 to be observed. Send instructions. In this environmental control instruction, only the time change of the target saturation value may be used, and the set temperature and the set humidity for obtaining not only the time change information of the saturation value but also the time change of the saturation value can be obtained. Information on each time change of the above may also be included. When the control device 200 receives the environmental control instruction from the plant detection camera 1, the control device 200 can obtain information on the time change of the saturation value included in the environmental control instruction or each time change of the set temperature, the set humidity and the saturation value. As such, control of each device in the greenhouse VGH is initiated or maintained.

Although FIG. 36 has been described as an example in which both the set temperature and the set humidity are changed by the user's operation, the environmental conditions for changing at least one of the set temperature and the set humidity may be controlled.

Next, the operation procedure for controlling the environmental conditions around the plant PT of the plant detection camera 1 of the third embodiment will be described with reference to FIG. 37. FIG. 37 is a flowchart illustrating an example of a control operation procedure for the ambient environmental conditions of the plant according to the third embodiment.

In FIG. 37, every time the threshold setting / moisture index detection processing unit 27a calculates the moisture index (standardized pixel average moisture index or standardized moisture index sum) of the leaf PT3 (S111), the control unit 11 is calculated in step S111. The most recently calculated moisture index of K (K: 2 or more natural numbers) including the moisture index of leaf PT3 is acquired (S112). That is, the control unit 11 can recognize the transition of the increase / decrease in the water index of the leaf PT3 by step S112. If the control unit 11 has acquired only one moisture index, the control unit 11 does not perform the processes after step S112 until two or more moisture indexes are acquired.

The control unit 11 determines whether or not the transition of the increase / decrease of the K water index matches the transition shown in the predetermined water stress profile (S113). The predetermined water stress profile is, for example, any one of the water stress profiles shown in FIGS. 33 (A) to 33 (D), and the farmer who is the user increases the sugar content in the growth of the plant PT (for example, tomato). It is a water stress profile that I think is necessary for this.

When the control unit 11 determines that the transition of the increase / decrease of the K water index matches the transition shown in the predetermined water stress profile (S113, YES), the leaf PT3 evaporates so as to follow the predetermined water stress profile. Assuming that the environment control instruction is generated including the maintenance of the surrounding environmental conditions (for example, temperature and humidity), the maintenance instruction is transmitted to the control device 200 (S114).

On the other hand, when the control unit 11 determines that the transition of the increase / decrease of the K water index does not match the transition shown in the predetermined water stress profile (S113, NO), the leaf PT3 follows the predetermined water stress profile. Assuming that it is not transpired, an environmental control instruction including a change in the surrounding environmental conditions (for example, temperature and humidity) is generated, and the maintenance instruction is transmitted to the control device 200 (S115).

If the control of the water potential (that is, the measurement of the water potential) is not completed (S116, NO), the process of the plant detection camera 1 returns to step S111 and steps until the control of the water potential (that is, the measurement of the water index) is completed. The processes of S111 to S115 are repeated. On the other hand, when the control of the water potential (that is, the measurement of the water content index) is completed (S116, YES), the process shown in FIG. 37 is completed.

As described above, the plant detection camera 1 of the third embodiment is connected to the control device 200 for controlling the environmental conditions (for example, temperature and humidity) around the leaf PT3 of the plant PT to be observed, and is calculated. Based on the transition of increase / decrease in the water content index (for example, the standardized pixel average water content index) as the water content contained in the leaf PT3, the control device 200 is instructed to change or instruct the environmental conditions at the time of calculating the latest water content index.

As a result, the plant detection camera 1 obtains a water index according to the water stress profile according to the user's preference, taking into consideration the environmental conditions (for example, temperature and humidity) around the leaf that determine the amount of transpiration of the leaf. If not, the control device 200 can be instructed to change the environmental conditions around the leaf PT3 in the greenhouse VGH. In other words, the plant detection camera 1 instructs the maintenance or change of the environmental conditions around the leaf PT3 in the greenhouse VGH according to the user's preference including, for example, the irrigation timing for obtaining a high sugar content. It is possible to support the creation of an environment that applies water stress according to the water stress profile.

Further, the plant detection camera 1 displays the transition of the increase / decrease in the amount of water contained in the leaf PT3 of the plant PT from the start to the end of the control (measurement) of the water potential on the monitor 50 in chronological order. As a result, the plant detection camera 1 quantifies the transition of the water content contained in the plant by displaying a graph showing the time-series transition of the water content contained in the leaf PT3 of the plant PT on the UI screen 60 of the monitor 50. It can be presented in a timely manner.

Further, the environmental condition is the temperature around the leaf PT3 to be observed, and the plant detection camera 1 transmits a change instruction to raise or lower the temperature around the leaf PT3 to the control device 200. As a result, the control device 200 raises the temperature around the leaf PT3 by controlling each device connected to the control device 200 in the greenhouse VGH in response to the change instruction from the plant detection camera 1. It can be lowered or lowered. The plant detection camera 1 can obtain a water index according to the water stress profile according to the user's preference after the temperature is controlled up and down in the control device 200.

Further, the environmental condition is the humidity around the leaf PT3 to be observed, and the plant detection camera 1 transmits a change instruction to raise or lower the humidity around the leaf PT3 to the control device 200. As a result, the control device 200 raises the humidity around the leaf PT3 by controlling each device connected to the control device 200 in the vinyl house VGH in response to the change instruction from the plant detection camera 1. It can be lowered or lowered. The plant detection camera 1 can obtain a water index according to the water stress profile according to the user's preference after the humidity is controlled up and down in the control device 200.

Further, the environmental conditions are the temperature and humidity around the leaf PT3 to be observed, and the plant detection camera 1 raises the temperature around the leaf PT3 and lowers the humidity, or lowers the temperature around the leaf PT3. In addition, a change instruction to raise the humidity is transmitted to the control device 200. As a result, the control device 200 raises the temperature around the leaf PT3 by controlling each device connected to the control device 200 in the greenhouse VGH in response to the change instruction from the plant detection camera 1. Moreover, it is possible to lower the humidity, or lower the temperature around the leaf PT3 and raise the humidity. The plant detection camera 1 can obtain a water index according to the water stress profile according to the user's preference after the temperature and humidity are controlled up and down in the control device 200.

Further, the environmental condition is the temperature and humidity around the leaf PT3 to be observed, but the plant detection camera 1 transmits a maintenance instruction to maintain the temperature and humidity around the leaf PT3 to the control device 200. .. As a result, the control device 200 controls the temperature and humidity around the leaf PT3 by controlling each device connected to the control device 200 in the greenhouse VGH in response to the maintenance instruction from the plant detection camera 1. It becomes possible to maintain. The plant detection camera 1 can obtain a water index according to the water stress profile according to the user's preference after the temperature and humidity are maintained and controlled by the control device 200.

Further, on the leaf PT3 of the plant PT, a white background plate bd that covers the back surface of the leaf PT3 of the plant PT is arranged when viewed from the first projection light source 13 and the second projection light source 15. As a result, the plant detection camera 1 can perform scattered light (for example, outside sunlight, etc.) from the surrounding leaves even in a leaf group in which a large number of leaves are overgrown around the leaf PT3 which is the target site for observing the plant. Since the influence of light scattering) can be eliminated, the water content of leaf PT3 can be accurately measured.

Although various embodiments have been described above with reference to the drawings, it goes without saying that the present invention is not limited to such examples. It is clear that a person skilled in the art can come up with various modifications or modifications within the scope of the claims, which naturally belong to the technical scope of the present invention. Understood.

It should be noted that the cultivation apparatus of the present embodiment described above performs unirrigated treatment such as interrupting irrigation of plants in order to apply stress (for example, water stress) to plants (for example, tomato leaves). explained. However, in the cultivation apparatus of the present embodiment, the method of applying stress to plants (for example, water stress) is not limited to unirrigated. For example, in the cultivation apparatus of the present embodiment, in order to apply stress to the plant (for example, water stress), the electric conductivity of the liquid fertilizer (that is, the liquid fertilizer) supplied to the plant instead of being unirrigated is set to a predetermined value or more. You may change it to be larger. That is, by changing the cultivation device so that the electric conductivity of the liquid fertilizer becomes larger than a predetermined value, as a result, water stress equivalent to that of unirrigated plants is given to the plants. This is because the electric conductivity of the liquid fertilizer changes so that it becomes larger than a predetermined value, so that the roots cannot absorb water due to the osmotic pressure (in other words, salt stress is applied), and as a result, it has not been achieved. This is because, as with irrigation, water stress is applied to the plants. The predetermined value is a known value obtained from the experience of the breeder, and is the lower limit value of the electric conductivity of the liquid fertilizer when salt stress is applied to the plant.

The present invention is useful as a water content observing device, a water content observing method, and a cultivation device capable of flexibly controlling the water content contained in a plant containing fruits such as tomatoes in consideration of the influence of surrounding environmental conditions. Is.

1 Plant detection camera 11 Control unit 11a Timing control unit 13 First projection light source 15 Second projection light source 17 Projection light source scanning optical unit 21, 31 Imaging optical unit 23, 33 Light receiving unit 25 Signal processing unit 25a I / V conversion circuit 25b Amplification circuit 25c Comparer / Peak hold processing unit 27 Detection processing unit 27a Threshold setting / Moisture index detection processing unit 27b Memory 27c Detection result filter processing unit 29 Display processing unit 35 Imaging signal processing unit 37 Display control unit 50 Monitor 60 UI (user interface) ) Screen 61 Search irrigation amount input screen 63 Setting area 64 Initial setting button 66 Misalignment threshold setting button 67, 68 Input box 71 Irrigation amount search mode button 72, 74 Display box 73 Water stress control (cultivation control) mode button 200 Control device 201 I / F unit 203 Built-in clock 205 Calculation processing unit 207 Storage unit 211 Environmental sensor 213, 215 Open / close valve 217 Water supply pump 219 Side window 221 Ventilation device 223 Ceiling curtain 225 Side curtain 227 Air conditioner 1000 Plant observation system BB Base bd, bdd White Background plate bd1 Opening bd2 Hole bd3, bd4, bd5, bd21 Slit bd11 Frame Bw Target range gh1, gh2 Graph Gm1 Leaf moisture monitoring screen JG Image judgment unit PT3, PT3t Leaf LS1 Reference optical LS2 Measurement optical MT communication terminal NVSS Invisible light sensor pf1, pf2, pf3, pf4 Water stress profile PJ Projector TR Light source scanning timing signal RF Light source emission signal RV0 Ambient light RV1, RV2 Diffuse reflected light VGH Vinyl house VSC Visible light camera WF Fertilizer water supply device

The present invention relates to a water content observation device for observing the amount of water contained in the plant, the plant detecting unit for irradiating a laser beam of a plurality of types of different wavelengths toward a moisture value computation portion before Symbol plants, before based on the plurality of types of reflected light reflected at each irradiation position of the serial plant, and water amount calculation unit which exits calculate the amount of moisture definitive moisture value computation portion of the plant, the environmental conditions around the plant The environmental control device is connected to the environmental control device to be controlled, and the change or maintenance of the environmental conditions is made to the environmental control device based on the transition of the increase / decrease in the water content in the water content calculation target part of the plant calculated by the water content calculation unit. Provided is a water content observing device including a control unit for instructing.

Further, the present invention provides a water content observation method in water content observation device for observing the amount of water contained in the plant, a laser beam of a plurality of types of different wavelengths toward a moisture value computation portion before Symbol plants and, based on the plurality of types of reflected light reflected at each irradiation position before Symbol plant issues calculate the amount of moisture definitive moisture value computation portion of the plant, controls the environmental conditions around the plant environment connected to the control device, definitive based on changes in moisture content increase or decrease in water content calculation target site of the calculated said plant, instructing a change or maintenance of the environmental conditions in the environment control apparatus, the water content observed method provide.

Claims (9)

It is a water content observation device that observes the amount of water contained in plants.
A first light source that irradiates the plant with reference light of the first wavelength, which has the property of being difficult to be absorbed by water by optical scanning.
A second light source that irradiates the plant with measurement light of a second wavelength having a characteristic of being easily absorbed by water by the optical scanning.
Water content calculation that repeatedly calculates the amount of water contained in the plant based on the reflected light of the reference light reflected by the plant and the reflected light of the measurement light reflected by the plant in a certain measurement period. Department and
It is connected to an environmental control device that controls the environmental conditions around the plant, and the change or maintenance of the environmental conditions is performed based on the transition of the increase / decrease in the water content contained in the plant calculated by the water content calculation unit. It is equipped with a control unit that instructs the environmental control device.
Moisture content observation device. The water content observing device according to claim 1.
The control unit displays on the display unit the transition of the increase / decrease in the amount of water contained in the plant from the start to the end of the measurement period calculated by the water content calculation unit in chronological order.
Moisture content observation device. The water content observing device according to claim 1.
The environmental condition is the ambient temperature of the plant.
The control unit transmits a change instruction to raise or lower the temperature around the plant to the environmental control device.
Moisture content observation device. The water content observing device according to claim 1.
The environmental condition is the humidity around the plant.
The control unit transmits a change instruction to raise or lower the humidity around the plant to the environmental control device.
Moisture content observation device. The water content observing device according to claim 1.
The environmental conditions are the temperature and humidity around the plant.
The control unit gives a change instruction to raise the temperature around the plant and lower the humidity around the plant, or a change instruction to lower the temperature around the plant and raise the humidity around the plant. Sending to the environmental control device,
Moisture content observation device. The water content observing device according to claim 1.
The control unit transmits a maintenance instruction not to change the environmental condition to the environmental control device.
Moisture content observation device. The water content observing device according to claim 1.
A background object covering the back surface of the plant is arranged on the plant when viewed from the first light source and the second light source.
Moisture content observation device. The water content observation device according to claim 1 and
A cultivation control unit for irrigating the plant with a predetermined amount of water based on a time-series transition of the water content calculated by the water content calculation unit in a part of the measurement period is provided.
Cultivation equipment. It is a water content observation method in a water content observation device for observing the water content contained in a plant.
The first light source irradiates the plant with reference light having a first wavelength having a property of being difficult to be absorbed by water by optical scanning.
The second light source irradiates the plant with measurement light having a second wavelength having a characteristic of being easily absorbed by water by the optical scanning.
In a certain measurement period, the amount of water contained in the plant is repeatedly calculated based on the reflected light of the reference light reflected by the plant and the reflected light of the measurement light reflected by the plant.
Connected to an environmental control device that controls the environmental conditions around the plant,
Instruct the environmental control device to change or maintain the environmental conditions based on the calculated transition of the increase / decrease in the amount of water contained in the plant.
Moisture content observation method.